1
|
Morris SM, Wiens L, Rose O, Fritz G, Rogers T, Gebhard S. Regulatory interactions between daptomycin- and bacitracin-responsive pathways coordinate the cell envelope antibiotic resistance response of Enterococcus faecalis. Mol Microbiol 2024; 121:1148-1163. [PMID: 38646792 DOI: 10.1111/mmi.15264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 04/02/2024] [Accepted: 04/03/2024] [Indexed: 04/23/2024]
Abstract
Enterococcal infections frequently show high levels of antibiotic resistance, including to cell envelope-acting antibiotics like daptomycin (DAP). While we have a good understanding of the resistance mechanisms, less is known about the control of such resistance genes in enterococci. Previous work unveiled a bacitracin resistance network, comprised of the sensory ABC transporter SapAB, the two-component system (TCS) SapRS and the resistance ABC transporter RapAB. Interestingly, components of this system have recently been implicated in DAP resistance, a role usually regulated by the TCS LiaFSR. To better understand the regulation of DAP resistance and how this relates to mutations observed in DAP-resistant clinical isolates of enterococci, we here explored the interplay between these two regulatory pathways. Our results show that SapR regulates an additional resistance operon, dltXABCD, a known DAP resistance determinant, and show that LiaFSR regulates the expression of sapRS. This regulatory structure places SapRS-target genes under dual control, where expression is directly controlled by SapRS, which itself is up-regulated through LiaFSR. The network structure described here shows how Enterococcus faecalis coordinates its response to cell envelope attack and can explain why clinical DAP resistance often emerges via mutations in regulatory components.
Collapse
Affiliation(s)
- Sali M Morris
- Life Sciences Department, Milner Centre for Evolution, University of Bath, Bath, UK
| | - Laura Wiens
- Institute of Molecular Physiology, Johannes-Gutenberg-University Mainz, Mainz, Germany
| | - Olivia Rose
- Life Sciences Department, Milner Centre for Evolution, University of Bath, Bath, UK
| | - Georg Fritz
- School of Molecular Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Tim Rogers
- Department of Mathematical Sciences, University of Bath, Bath, UK
| | - Susanne Gebhard
- Life Sciences Department, Milner Centre for Evolution, University of Bath, Bath, UK
- Institute of Molecular Physiology, Johannes-Gutenberg-University Mainz, Mainz, Germany
| |
Collapse
|
2
|
Tan J, Zhu C, Li L, Wang J, Xia XH, Wang C. Engineering Cell Membranes: From Extraction Strategies to Emerging Biosensing Applications. Anal Chem 2024; 96:7880-7894. [PMID: 38272835 DOI: 10.1021/acs.analchem.3c01746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Affiliation(s)
- Jing Tan
- College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, P.R. China
| | - Chengcheng Zhu
- College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, P.R. China
| | - Lulu Li
- College of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212000, P.R. China
| | - Jin Wang
- College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, P.R. China
| | - Xing-Hua Xia
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing 210023, P.R. China
| | - Chen Wang
- College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, P.R. China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing 210023, P.R. China
| |
Collapse
|
3
|
Singh KV, Galloway-Peña J, Montealegre MC, Dong X, Murray BE. Genomic context as well as sequence of both psr and penicillin-binding protein 5 contributes to β-lactam resistance in Enterococcus faecium. mBio 2024; 15:e0017024. [PMID: 38564699 PMCID: PMC11077988 DOI: 10.1128/mbio.00170-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 03/04/2024] [Indexed: 04/04/2024] Open
Abstract
Penicillin-binding protein 5 (PBP5) of Enterococcus faecium (Efm) is vital for ampicillin resistance (AMP-R). We previously designated three forms of PBP5, namely, PBP5-S in Efm clade B strains [ampicillin susceptible (AMP-S)], PBP5-S/R (AMP-S or R), and PBP5-R (AMP-R) in clade A strains. Here, pbp5 deletion resulted in a marked reduction in AMP minimum inhibitory concentrations (MICs) to 0.01-0.09 µg/mL for clade B and 0.12-0.19 µg/mL for clade A strains; in situ complementation restored parental AMP MICs. Using D344SRF (lacking ftsW/psr/pbp5), constructs with ftsWA/psrA (from a clade A1 strain) cloned upstream of pbp5-S and pbp5-S/R alleles resulted in modest increases in MICs to 3-8 µg/mL, while high MICs (>64 µg/mL) were seen using pbp5 from A1 strains. Next, using ftsW ± psr from clade B and clade A/B and B/A hybrid constructs, the presence of psrB, even alone or in trans, resulted in much lower AMP MICs (3-8 µg/mL) than when psrA was present (MICs >64 µg/mL). qRT PCR showed relatively greater pbp5 expression (P = 0.007) with pbp5 cloned downstream of clade A1 ftsW/psr (MIC >128 µg/mL) vs when cloned downstream of clade B ftsW/psr (MIC 4-16 µg/mL), consistent with results in western blots. In conclusion, we report the effect of clade A vs B psr on AMP MICs as well as the impact of pbp5 alleles from different clades. While previously, Psr was not thought to contribute to AMP MICs in Efm, our results showed that the presence of psrB resulted in a major decrease in Efm AMP MICs. IMPORTANCE The findings of this study shed light on ampicillin resistance in Enterococcus faecium clade A strains. They underscore the significance of alterations in the amino acid sequence of penicillin-binding protein 5 (PBP5) and the pivotal role of the psr region in PBP5 expression and ampicillin resistance. Notably, the presence of a full-length psrB leads to reduced PBP5 expression and lower minimum inhibitory concentrations (MICs) of ampicillin compared to the presence of a shorter psrA, regardless of the pbp5 allele involved. Additionally, clade B E. faecium strains exhibit lower AMP MICs when both psr alleles from clades A and B are present, although it is important to consider other distinctions between clade A and B strains that may contribute to this effect. It is intriguing to note that the divergence between clade A and clade B E. faecium and the subsequent evolution of heightened AMP MICs in hospital-associated strains appear to coincide with changes in Pbp5 and psr. These changes in psr may have resulted in an inactive Psr, facilitating increased PBP5 expression and greater ampicillin resistance. These results raise the possibility that a mimicker of PsrB, if one could be designed, might be able to lower MICs of ampicillin-resistant E. faecium, thus potentially resorting ampicillin to our therapeutic armamentarium for this species.
Collapse
Affiliation(s)
- Kavindra V. Singh
- Division of Infectious Diseases, Department of Internal Medicine, University of Texas Health Science Center, Houston, Texas, USA
| | - Jessica Galloway-Peña
- Division of Infectious Diseases, Department of Internal Medicine, University of Texas Health Science Center, Houston, Texas, USA
| | - Maria Camila Montealegre
- Division of Infectious Diseases, Department of Internal Medicine, University of Texas Health Science Center, Houston, Texas, USA
- Department of Microbiology and Infectious Diseases, University of Texas Health Science Center, Houston, Texas, USA
| | - Xingxing Dong
- Division of Infectious Diseases, Department of Internal Medicine, University of Texas Health Science Center, Houston, Texas, USA
| | - Barbara E. Murray
- Division of Infectious Diseases, Department of Internal Medicine, University of Texas Health Science Center, Houston, Texas, USA
- Department of Microbiology and Infectious Diseases, University of Texas Health Science Center, Houston, Texas, USA
| |
Collapse
|
4
|
Nair ZJ, Gao IH, Firras A, Chong KKL, Hill ED, Choo PY, Colomer-Winter C, Chen Q, Manzano C, Pethe K, Kline KA. An essential protease, FtsH, influences daptomycin resistance acquisition in Enterococcus faecalis. Mol Microbiol 2024; 121:1021-1038. [PMID: 38527904 DOI: 10.1111/mmi.15253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 03/11/2024] [Accepted: 03/11/2024] [Indexed: 03/27/2024]
Abstract
Daptomycin is a last-line antibiotic commonly used to treat vancomycin-resistant Enterococci, but resistance evolves rapidly and further restricts already limited treatment options. While genetic determinants associated with clinical daptomycin resistance (DAPR) have been described, information on factors affecting the speed of DAPR acquisition is limited. The multiple peptide resistance factor (MprF), a phosphatidylglycerol-modifying enzyme involved in cationic antimicrobial resistance, is linked to DAPR in pathogens such as methicillin-resistant Staphylococcus aureus. Since Enterococcus faecalis encodes two paralogs of mprF and clinical DAPR mutations do not map to mprF, we hypothesized that functional redundancy between the paralogs prevents mprF-mediated resistance and masks other evolutionary pathways to DAPR. Here, we performed in vitro evolution to DAPR in mprF mutant background. We discovered that the absence of mprF results in slowed DAPR evolution and is associated with inactivating mutations in ftsH, resulting in the depletion of the chaperone repressor HrcA. We also report that ftsH is essential in the parental, but not in the ΔmprF, strain where FtsH depletion results in growth impairment in the parental strain, a phenotype associated with reduced extracellular acidification and reduced ability for metabolic reduction. This presents FtsH and HrcA as enticing targets for developing anti-resistance strategies.
Collapse
Affiliation(s)
- Zeus Jaren Nair
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Drug Resistance Interdisciplinary Research Group, Singapore, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- Interdisciplinary Graduate Programme, Graduate College, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Iris Hanxing Gao
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Aslam Firras
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Kelvin Kian Long Chong
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- Interdisciplinary Graduate Programme, Graduate College, Nanyang Technological University, Singapore, Singapore
| | - Eric D Hill
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, Singapore
| | - Pei Yi Choo
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Cristina Colomer-Winter
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Qingyan Chen
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Caroline Manzano
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Kevin Pethe
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Drug Resistance Interdisciplinary Research Group, Singapore, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
- National Centre for Infectious Diseases (NCID), Singapore, Singapore
| | - Kimberly A Kline
- Singapore-MIT Alliance for Research and Technology, Antimicrobial Drug Resistance Interdisciplinary Research Group, Singapore, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| |
Collapse
|
5
|
Karapetian M, Alimbarashvili E, Vishnepolsky B, Gabrielian A, Rosenthal A, Hurt DE, Tartakovsky M, Mchedlishvili M, Arsenadze D, Pirtskhalava M, Zaalishvili G. Evaluation of the synergistic potential and mechanisms of action for de novo designed cationic antimicrobial peptides. Heliyon 2024; 10:e27852. [PMID: 38560672 PMCID: PMC10979160 DOI: 10.1016/j.heliyon.2024.e27852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 03/01/2024] [Accepted: 03/07/2024] [Indexed: 04/04/2024] Open
Abstract
Antimicrobial peptides (AMPs) have emerged as promising candidates in combating antimicrobial resistance - a growing issue in healthcare. However, to develop AMPs into effective therapeutics, a thorough analysis and extensive investigations are essential. In this study, we employed an in silico approach to design cationic AMPs de novo, followed by their experimental testing. The antibacterial potential of de novo designed cationic AMPs, along with their synergistic properties in combination with conventional antibiotics was examined. Furthermore, the effects of bacterial inoculum density and metabolic state on the antibacterial activity of AMPs were evaluated. Finally, the impact of several potent AMPs on E. coli cell envelope and genomic DNA integrity was determined. Collectively, this comprehensive analysis provides insights into the unique characteristics of cationic AMPs.
Collapse
Affiliation(s)
- Margarita Karapetian
- Laboratory of Chromatin Biology, Institute of Cellular and Molecular Biology, Agricultural University of Georgia, 240 David Aghmashenebeli Alley, 0159, Tbilisi, Georgia
| | - Evgenia Alimbarashvili
- Laboratory of Chromatin Biology, Institute of Cellular and Molecular Biology, Agricultural University of Georgia, 240 David Aghmashenebeli Alley, 0159, Tbilisi, Georgia
- Ivane Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
| | - Boris Vishnepolsky
- Ivane Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
| | - Andrei Gabrielian
- Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Alex Rosenthal
- Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Darrell E. Hurt
- Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Michael Tartakovsky
- Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Mariam Mchedlishvili
- Laboratory of Chromatin Biology, Institute of Cellular and Molecular Biology, Agricultural University of Georgia, 240 David Aghmashenebeli Alley, 0159, Tbilisi, Georgia
| | - Davit Arsenadze
- Laboratory of Chromatin Biology, Institute of Cellular and Molecular Biology, Agricultural University of Georgia, 240 David Aghmashenebeli Alley, 0159, Tbilisi, Georgia
| | - Malak Pirtskhalava
- Ivane Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
| | - Giorgi Zaalishvili
- Laboratory of Chromatin Biology, Institute of Cellular and Molecular Biology, Agricultural University of Georgia, 240 David Aghmashenebeli Alley, 0159, Tbilisi, Georgia
- Ivane Beritashvili Center of Experimental Biomedicine, 0160, Tbilisi, Georgia
| |
Collapse
|
6
|
Zbylicki BR, Murphy CE, Petsche JA, Müh U, Dobrila HA, Ho TD, Daum MN, Pannullo AG, Weiss DS, Ellermeier CD. Identification of Clostridioides difficile mutants with increased daptomycin resistance. J Bacteriol 2024; 206:e0036823. [PMID: 38376203 PMCID: PMC10955854 DOI: 10.1128/jb.00368-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 01/20/2024] [Indexed: 02/21/2024] Open
Abstract
Daptomycin is a cyclic lipopeptide antibiotic used to treat infections caused by some Gram-positive bacteria. Daptomycin disrupts synthesis of the peptidoglycan (PG) cell wall by inserting into the cytoplasmic membrane and binding multiple forms of the undecaprenyl carrier lipid required for PG synthesis. Membrane insertion requires phosphatidylglycerol, so studies of daptomycin can provide insight into assembly and maintenance of the cytoplasmic membrane. Here, we studied the effects of daptomycin on Clostridioides difficile, the leading cause of healthcare-associated diarrhea. We observed that growth of C. difficile strain R20291 in the presence of sub-MIC levels of daptomycin resulted in a chaining phenotype, minicell formation, and lysis-phenotypes broadly consistent with perturbation of membranes and PG synthesis. We also selected for and characterized eight mutants with elevated daptomycin resistance. The mutations in these mutants were mapped to four genes: cdsA (cdr20291_2041), ftsH2 (cdr20291_3396), esrR (cdr20291_1187), and draS (cdr20291_2456). Of these four genes, only draS has been characterized previously. Follow-up studies indicate these mutations confer daptomycin resistance by two general mechanisms: reducing the amount of phosphatidylglycerol in the cytoplasmic membrane (cdsA) or altering the regulation of membrane processes (ftsH2, esrR, and draS). Thus, the mutants described here provide insights into phospholipid synthesis and identify signal transduction systems involved in cell envelope biogenesis and stress response in C. difficile. IMPORTANCE C. difficile is the leading cause of healthcare-associated diarrhea and is a threat to public health due to the risk of recurrent infections. Understanding biosynthesis of the atypical cell envelope of C. difficile may provide insight into novel drug targets to selectively inhibit C. difficile. Here, we identified mutations that increased daptomycin resistance and allowed us to better understand phospholipid synthesis, cell envelope biogenesis, and stress response in C. difficile.
Collapse
Affiliation(s)
- Brianne R. Zbylicki
- Department of Microbiology and Immunology, The University of Iowa, Iowa City, Iowa, USA
| | - Claire E. Murphy
- Department of Microbiology and Immunology, The University of Iowa, Iowa City, Iowa, USA
| | - Jennifer A. Petsche
- Interdisciplinary Graduate Program in Molecular Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Ute Müh
- Department of Microbiology and Immunology, The University of Iowa, Iowa City, Iowa, USA
| | - Horia A. Dobrila
- Department of Microbiology and Immunology, The University of Iowa, Iowa City, Iowa, USA
| | - Theresa D. Ho
- Department of Microbiology and Immunology, The University of Iowa, Iowa City, Iowa, USA
| | - Mikaela N. Daum
- Department of Microbiology and Immunology, The University of Iowa, Iowa City, Iowa, USA
| | - Anthony G. Pannullo
- Department of Microbiology and Immunology, The University of Iowa, Iowa City, Iowa, USA
| | - David S. Weiss
- Department of Microbiology and Immunology, The University of Iowa, Iowa City, Iowa, USA
| | - Craig D. Ellermeier
- Department of Microbiology and Immunology, The University of Iowa, Iowa City, Iowa, USA
- Graduate Program in Genetics, University of Iowa, Iowa City, Iowa, USA
| |
Collapse
|
7
|
Axell-House DB, Simar SR, Panesso D, Rincon S, Miller WR, Khan A, Pemberton OA, Valdez L, Nguyen AH, Hood KS, Rydell K, DeTranaltes AM, Jones MN, Atterstrom R, Reyes J, Sahasrabhojane PV, Suleyman G, Zervos M, Shelburne SA, Singh KV, Shamoo Y, Hanson BM, Tran TT, Arias CA. LiaX is a surrogate marker for cell envelope stress and daptomycin non-susceptibility in Enterococcus faecium. Antimicrob Agents Chemother 2024; 68:e0106923. [PMID: 38289081 PMCID: PMC10916372 DOI: 10.1128/aac.01069-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 12/20/2023] [Indexed: 02/12/2024] Open
Abstract
Daptomycin (DAP) is often used as a first-line therapy to treat vancomycin-resistant Enterococcus faecium infections, but emergence of DAP non-susceptibility threatens the effectiveness of this antibiotic. Moreover, current methods to determine DAP minimum inhibitory concentrations (MICs) have poor reproducibility and accuracy. In enterococci, DAP resistance is mediated by the LiaFSR cell membrane stress response system, and deletion of liaR encoding the response regulator results in hypersusceptibility to DAP and antimicrobial peptides. The main genes regulated by LiaR are a cluster of three genes, designated liaXYZ. In Enterococcus faecalis, LiaX is surface-exposed with a C-terminus that functions as a negative regulator of cell membrane remodeling and an N-terminal domain that is released to the extracellular medium where it binds DAP. Thus, in E. faecalis, LiaX functions as a sentinel molecule recognizing DAP and controlling the cell membrane response, but less is known about LiaX in E. faecium. Here, we found that liaX is essential in E. faecium with an activated LiaFSR system. Unlike E. faecalis, E. faecium LiaX is not detected in the extracellular milieu and does not appear to alter phospholipid architecture. We further postulated that LiaX could be used as a surrogate marker for cell envelope activation and non-susceptibility to DAP. For this purpose, we developed and optimized a LiaX enzyme-linked immunosorbent assay (ELISA). We then assessed 86 clinical E. faecium bloodstream isolates for DAP MICs and used whole genome sequencing to assess for substitutions in LiaX. All DAP-resistant clinical strains of E. faecium exhibited elevated LiaX levels. Strikingly, 73% of DAP-susceptible isolates by standard MIC determination also had elevated LiaX ELISAs compared to a well-characterized DAP-susceptible strain. Phylogenetic analyses of predicted amino acid substitutions showed 12 different variants of LiaX without a specific association with DAP MIC or LiaX ELISA values. Our findings also suggest that many E. faecium isolates that test DAP susceptible by standard MIC determination are likely to have an activated cell stress response that may predispose to DAP failure. As LiaX appears to be essential for the cell envelope response to DAP, its detection could prove useful to improve the accuracy of susceptibility testing by anticipating therapeutic failure.
Collapse
Affiliation(s)
- Dierdre B. Axell-House
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Medicine, Weill Cornell Medical College, New York, New York, USA
| | - Shelby R. Simar
- Center for Infectious Diseases, University of Texas Health Science Center, School of Public Health, Houston, Texas, USA
| | - Diana Panesso
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Medicine, Weill Cornell Medical College, New York, New York, USA
- Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogotá, Colombia
| | - Sandra Rincon
- Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogotá, Colombia
| | - William R. Miller
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Medicine, Weill Cornell Medical College, New York, New York, USA
| | - Ayesha Khan
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | | | - Lizbet Valdez
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
| | - April H. Nguyen
- McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Kara S. Hood
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
| | - Kirsten Rydell
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
| | - Andrea M. DeTranaltes
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
| | - Mary N. Jones
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
| | - Rachel Atterstrom
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
| | - Jinnethe Reyes
- Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogotá, Colombia
| | - Pranoti V. Sahasrabhojane
- Department of Infectious Diseases, Infection Control, and Employee Health, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Geehan Suleyman
- Department of Internal Medicine, Division of Infectious Diseases, Henry Ford Hospital, Detroit, Michigan, USA
| | - Marcus Zervos
- Department of Internal Medicine, Division of Infectious Diseases, Henry Ford Hospital, Detroit, Michigan, USA
| | - Samuel A. Shelburne
- Department of Infectious Diseases, Infection Control, and Employee Health, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
- Department of Genomic Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Kavindra V. Singh
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Medicine, Weill Cornell Medical College, New York, New York, USA
| | - Yousif Shamoo
- Department of Biosciences, Rice University, Houston, Texas, USA
| | - Blake M. Hanson
- Center for Infectious Diseases, University of Texas Health Science Center, School of Public Health, Houston, Texas, USA
| | - Truc T. Tran
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Medicine, Weill Cornell Medical College, New York, New York, USA
| | - Cesar A. Arias
- Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Medicine, Weill Cornell Medical College, New York, New York, USA
| |
Collapse
|
8
|
Salinas-Restrepo C, Naranjo-Duran AM, Quintana J, Bueno J, Guzman F, Hoyos Palacio LM, Segura C. Short Antimicrobial Peptide Derived from the Venom Gland Transcriptome of Pamphobeteus verdolaga Increases Gentamicin Susceptibility of Multidrug-Resistant Klebsiella pneumoniae. Antibiotics (Basel) 2023; 13:6. [PMID: 38275316 PMCID: PMC10812672 DOI: 10.3390/antibiotics13010006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/07/2023] [Accepted: 11/17/2023] [Indexed: 01/27/2024] Open
Abstract
Infectious diseases account for nine percent of annual human deaths, and the widespread emergence of antimicrobial resistances threatens to significantly increase this number in the coming decades. The prospect of antimicrobial peptides (AMPs) derived from venomous animals presents an interesting alternative for developing novel active pharmaceutical ingredients (APIs). Small, cationic and amphiphilic peptides were predicted from the venom gland transcriptome of Pamphobeteus verdolaga using a custom database of the arthropod's AMPs. Ninety-four candidates were chemically synthesized and screened against ATCC® strains of Escherichia coli and Staphylococcus aureus. Among them, one AMP, named PvAMP66, showed broad-spectrum antimicrobial properties with selectivity towards Gram-negative bacteria. It also exhibited activity against Pseudomonas aeruginosa, as well as both an ATCC® and a clinically isolated multidrug-resistant (MDR) strain of K. pneumoniae. The scanning electron microscopy analysis revealed that PvAMP66 induced morphological changes of the MDR K. pneumoniae strain suggesting a potential "carpet model" mechanism of action. The isobologram analysis showed an additive interaction between PvAMP66 and gentamicin in inhibiting the growth of MDR K. pneumoniae, leading to a ten-fold reduction in gentamicin's effective concentration. A cytotoxicity against erythrocytes or peripheral blood mononuclear cells was observed at concentrations three to thirteen-fold higher than those exhibited against the evaluated bacterial strains. This evidence suggests that PvAMP66 can serve as a template for the development of AMPs with enhanced activity and deserves further pre-clinical studies as an API in combination therapy.
Collapse
Affiliation(s)
- Cristian Salinas-Restrepo
- Grupo Toxinología, Alternativas Terapéuticas y Alimentarias, Facultad de Ciencias Farmacéuticas y Alimentarias, Universidad de Antioquia, Medellín 050012, Colombia; (C.S.-R.); (A.M.N.-D.)
| | - Ana María Naranjo-Duran
- Grupo Toxinología, Alternativas Terapéuticas y Alimentarias, Facultad de Ciencias Farmacéuticas y Alimentarias, Universidad de Antioquia, Medellín 050012, Colombia; (C.S.-R.); (A.M.N.-D.)
| | - Juan Quintana
- Facultad de Medicina, Universidad Cooperativa de Colombia, Medellín 050012, Colombia;
| | - Julio Bueno
- Grupo Reproducción, Facultad de Medicina, Universidad de Antioquia, Medellín 050012, Colombia;
| | - Fanny Guzman
- Núcleo Biotecnología Curauma (NBC), Pontificia Universidad Católica de Valparaíso, Valparaíso 3100000, Chile;
| | - Lina M. Hoyos Palacio
- Escuela de Ciencias de la Salud, Grupo de Investigación Biología de Sistemas, Universidad Pontificia Bolivariana, Medellín 050031, Colombia;
| | - Cesar Segura
- Grupo Malaria, Facultad de Medicina, Universidad de Antioquia, Medellín 050012, Colombia
| |
Collapse
|
9
|
Anurag Anand A, Amod A, Anwar S, Sahoo AK, Sethi G, Samanta SK. A comprehensive guide on screening and selection of a suitable AMP against biofilm-forming bacteria. Crit Rev Microbiol 2023:1-20. [PMID: 38102871 DOI: 10.1080/1040841x.2023.2293019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 11/30/2023] [Indexed: 12/17/2023]
Abstract
Lately, antimicrobial resistance (AMR) is increasing at an exponential rate making it important to search alternatives to antibiotics in order to combat multi-drug resistant (MDR) bacterial infections. Out of the several antibacterial and antibiofilm strategies being tested, antimicrobial peptides (AMPs) have shown to give better hopes in terms of a long-lasting solution to the problem. To select a desired AMP, it is important to make right use of available tools and databases that aid in identification, classification, and analysis of the physiochemical properties of AMPs. To identify the targets of these AMPs, it becomes crucial to understand their mode-of-action. AMPs can also be used in combination with other antibacterial and antibiofilm agents so as to achieve enhanced efficacy against bacteria and their biofilms. Due to concerns regarding toxicity, stability, and bioavailability, strategizing drug formulation at an early-stage becomes crucial. Although there are few concerns regarding development of bacterial resistance to AMPs, the evolution of resistance to AMPs occurs extremely slowly. This comprehensive review gives a deep insight into the selection of the right AMP, deciding the right target and combination strategy along with the type of formulation needed, and the possible resistance that bacteria can develop to these AMPs.
Collapse
Affiliation(s)
- Ananya Anurag Anand
- Department of Applied Sciences, Indian Institute of Information Technology Allahabad, Prayagraj, India
| | - Ayush Amod
- Department of Applied Sciences, Indian Institute of Information Technology Allahabad, Prayagraj, India
| | - Sarfraz Anwar
- Department of Bioinformatics, University of Allahabad, Prayagraj, India
| | - Amaresh Kumar Sahoo
- Department of Applied Sciences, Indian Institute of Information Technology Allahabad, Prayagraj, India
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Sintu Kumar Samanta
- Department of Applied Sciences, Indian Institute of Information Technology Allahabad, Prayagraj, India
| |
Collapse
|
10
|
Miller WR, Nguyen A, Singh KV, Rizvi S, Khan A, Erickson SG, Egge SL, Cruz M, Dinh AQ, Diaz L, Zhang R, Xu L, Garsin DA, Shamoo Y, Arias CA. Membrane Lipids Augment Cell Envelope Stress Signaling and Resistance to Antibiotics and Antimicrobial Peptides in Enterococcus faecalis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.17.562839. [PMID: 37904970 PMCID: PMC10614854 DOI: 10.1101/2023.10.17.562839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Enterococci have evolved resistance mechanisms to protect their cell envelopes against bacteriocins and host cationic antimicrobial peptides (CAMPs) produced in the gastrointestinal environment. Activation of the membrane stress response has also been tied to resistance to the lipopeptide antibiotic daptomycin. However, the actual effectors mediating resistance have not been elucidated. Here, we show that the MadRS (formerly YxdJK) membrane antimicrobial peptide defense system controls a network of genes, including a previously uncharacterized three gene operon (madEFG) that protects the E. faecalis cell envelope from antimicrobial peptides. Constitutive activation of the system confers protection against CAMPs and daptomycin in the absence of a functional LiaFSR system and leads to persistence of cardiac microlesions in vivo. Moreover, changes in the lipid cell membrane environment alter CAMP susceptibility and expression of the MadRS system. Thus, we provide a framework supporting a multilayered envelope defense mechanism for resistance and survival coupled to virulence.
Collapse
Affiliation(s)
- William R Miller
- Division of Infectious Diseases, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Medicine, Weill Cornell Medical College, New York, New York, USA
| | - April Nguyen
- Division of Infectious Diseases, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
- McGovern Medical School, University of Texas Health Science Center, Houston, TX, USA
- Microbiology and Molecular Genetics, Graduate School of Biomedical Sciences, University of Texas Health Science Center, Houston, TX, USA
| | - Kavindra V Singh
- Division of Infectious Diseases, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
| | - Samie Rizvi
- Division of Infectious Diseases, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
| | - Ayesha Khan
- McGovern Medical School, University of Texas Health Science Center, Houston, TX, USA
- Microbiology and Molecular Genetics, Graduate School of Biomedical Sciences, University of Texas Health Science Center, Houston, TX, USA
| | - Sam G Erickson
- McGovern Medical School, University of Texas Health Science Center, Houston, TX, USA
| | - Stephanie L Egge
- Division of Infectious Diseases, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
| | - Melissa Cruz
- McGovern Medical School, University of Texas Health Science Center, Houston, TX, USA
- Microbiology and Molecular Genetics, Graduate School of Biomedical Sciences, University of Texas Health Science Center, Houston, TX, USA
| | - An Q Dinh
- Division of Infectious Diseases, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
| | - Lorena Diaz
- Genomics and Resistant Microbes Group, Facultad de Medicina Clinica Alemana, Universidad del Desarrollo and Millennium Initiative for Collaborative Research On Bacterial Resistance (MICROB-R), Santiago, Chile
| | - Rutan Zhang
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
| | - Libin Xu
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington, USA
| | - Danielle A Garsin
- McGovern Medical School, University of Texas Health Science Center, Houston, TX, USA
- Microbiology and Molecular Genetics, Graduate School of Biomedical Sciences, University of Texas Health Science Center, Houston, TX, USA
| | - Yousif Shamoo
- Department of Biosciences, Rice University, Houston, TX, USA
| | - Cesar A Arias
- Division of Infectious Diseases, Houston Methodist Hospital, Houston, Texas, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Medicine, Weill Cornell Medical College, New York, New York, USA
- Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogota, Colombia
| |
Collapse
|
11
|
Zhang R, Ashford NK, Li A, Ross DH, Werth BJ, Xu L. High-throughput analysis of lipidomic phenotypes of methicillin-resistant Staphylococcus aureus by coupling in situ 96-well cultivation and HILIC-ion mobility-mass spectrometry. Anal Bioanal Chem 2023; 415:6191-6199. [PMID: 37535099 PMCID: PMC11059195 DOI: 10.1007/s00216-023-04890-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 07/23/2023] [Accepted: 07/25/2023] [Indexed: 08/04/2023]
Abstract
Antimicrobial resistance is a major threat to human health as resistant pathogens spread globally, and the development of new antimicrobials is slow. Since many antimicrobials function by targeting cell wall and membrane components, high-throughput lipidomics for bacterial phenotyping is of high interest for researchers to unveil lipid-mediated pathways when dealing with a large number of lab-selected or clinical strains. However, current practice for lipidomic analysis requires the cultivation of bacteria on a large scale, which does not replicate the growth conditions for high-throughput bioassays that are normally carried out in 96-well plates, such as susceptibility tests, growth curve measurements, and biofilm quantitation. Analysis of bacteria grown under the same condition as other bioassays would better inform the differences in susceptibility and other biological metrics. In this work, a high-throughput method for cultivation and lipidomic analysis of antimicrobial-resistant bacteria was developed for standard 96-well plates exemplified by methicillin-resistant Staphylococcus aureus (MRSA). By combining a 30-mm liquid chromatography (LC) column with ion mobility (IM) separation, elution time could be dramatically shortened to 3.6 min for a single LC run without losing major lipid features. Peak capacity was largely rescued by the addition of the IM dimension. Through multi-linear calibration, the deviation of retention time can be limited to within 5%, making database-based automatic lipid identification feasible. This high-throughput method was further validated by characterizing the lipidomic phenotypes of antimicrobial-resistant mutants derived from the MRSA strain, W308, grown in a 96-well plate.
Collapse
Affiliation(s)
- Rutan Zhang
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Nate K Ashford
- Department of Pharmacy, University of Washington, Seattle, WA, 98195, USA
| | - Amy Li
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Dylan H Ross
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, 98195, USA
- Biological Sciences Division, Pacific Northwest National Laboratory, WA, 99352, Richland, USA
| | - Brian J Werth
- Department of Pharmacy, University of Washington, Seattle, WA, 98195, USA
| | - Libin Xu
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, 98195, USA.
| |
Collapse
|
12
|
Axell-House DB, Simar SR, Panesso D, Rincon S, Miller WR, Khan A, Pemberton OA, Valdez L, Nguyen AH, Hood KS, Rydell K, DeTranaltes AM, Jones MN, Atterstrom R, Reyes J, Sahasrabhojane PV, Suleyman G, Zervos M, Shelburne SA, Singh KV, Shamoo Y, Hanson BM, Tran TT, Arias CA. LiaX is a surrogate marker for cell-envelope stress and daptomycin non-susceptibility in Enterococcus faecium. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.18.553907. [PMID: 37645818 PMCID: PMC10462152 DOI: 10.1101/2023.08.18.553907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Daptomycin (DAP) is often used as a first line therapy to treat vancomycin-resistant Enterococcus faecium (VR Efm ) infections but emergence of DAP non-susceptibility threatens the effectiveness of this antibiotic. Moreover, current methods to determine DAP MICs have poor reproducibility and accuracy. In enterococci, DAP resistance is mediated by the LiaFSR cell membrane stress response system and deletion of liaR encoding the response regulator results in hypersusceptibility to DAP and antimicrobial peptides. The main genes regulated by LiaR are a cluster of three genes, designated liaXYZ . In Enterococcus faecalis , LiaX is surface exposed with a C-terminus that functions as a negative regulator of cell membrane remodeling and an N-terminal domain that is released to the extracellular medium where it binds DAP. Thus, in E. faecalis , LiaX functions as a sentinel molecule recognizing DAP and controlling the cell membrane response, but less is known about LiaX in E. faecium . Here, we found that liaX is essential in E. faecium ( Efm ) with an activated LiaFSR system. Unlike E. faecalis , Efm LiaX is not detected in the extracellular milieu and does not appear to alter phospholipid architecture. We further postulated that LiaX could be used as a surrogate marker for cell envelope activation and non-susceptibility to DAP. For this purpose, we developed and optimized a LiaX ELISA. We then assessed 86 clinical E. faecium BSI isolates for DAP MICs and used whole genome sequencing to assess for substitutions in LiaX. All DAP-R clinical strains of E. faecium exhibited elevated LiaX levels. Strikingly, 73% of DAP-S isolates by standard MIC determination had elevated LiaX ELISAs above the established cut-off. Phylogenetic analyses of predicted amino acid substitutions showed 12 different variants of LiaX without a specific association with DAP MIC or LiaX ELISA values. Our findings also suggest that many Efm isolates that test DAP susceptible by standard MIC determination are likely to have an activated cell stress response that may predispose to DAP failure. As LiaX appears to be essential for the cell envelope response to DAP, its detection could prove useful to improve the accuracy of susceptibility testing by anticipating therapeutic failure.
Collapse
|
13
|
Nguyen AH, Tran TT, Panesso D, Hood K, Polamraju V, Zhang R, Khan A, Miller WR, Mileykovskaya E, Shamoo Y, Xu L, Vitrac H, Arias CA. Molecular Basis of Cell Membrane Adaptation in Daptomycin-Resistant Enterococcus faecalis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.02.551704. [PMID: 37577577 PMCID: PMC10418189 DOI: 10.1101/2023.08.02.551704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Daptomycin is a last-resort lipopeptide antibiotic that disrupts cell membrane (CM) and peptidoglycan homeostasis. Enterococcus faecalis has developed a sophisticated mechanism to avoid daptomycin killing by re-distributing CM anionic phospholipids away from the septum. The CM changes are orchestrated by a three-component regulatory system, designated LiaFSR, with a possible contribution of cardiolipin synthase (Cls). However, the mechanism by which LiaFSR controls the CM response and the role of Cls are unknown. Here, we show that cardiolipin synthase activity is essential for anionic phospholipid redistribution and daptomycin resistance since deletion of the two genes ( cls1 and cls2 ) encoding Cls abolished CM remodeling. We identified LiaY, a transmembrane protein regulated by LiaFSR, as an important mediator of CM remodeling required for re-distribution of anionic phospholipid microdomains via interactions with Cls1. Together, our insights provide a mechanistic framework on the enterococcal response to cell envelope antibiotics that could be exploited therapeutically.
Collapse
|
14
|
Liu Y, Ning Y, Chen Z, Han P, Zhi T, Li S, Ma A, Jia Y. Transcriptomics reveals substance biosynthesis and transport on membranes of Listeria monocytogenes affected by antimicrobial lipopeptide brevilaterin B. FOOD SCIENCE AND HUMAN WELLNESS 2023. [DOI: 10.1016/j.fshw.2022.10.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
15
|
Fitzgerald BA, Wadud A, Slimak Z, Slonczewski JL. Enterococcus faecalis OG1RF Evolution at Low pH Selects Fusidate-Sensitive Mutants in Elongation Factor G and at High pH Selects Defects in Phosphate Transport. Appl Environ Microbiol 2023; 89:e0046623. [PMID: 37272807 PMCID: PMC10304957 DOI: 10.1128/aem.00466-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 05/15/2023] [Indexed: 06/06/2023] Open
Abstract
Enterococcus bacteria inhabit human and soil environments that show a wide range of pH values. Strains include commensals as well as antibiotic-resistant pathogens. We investigated the adaptation to pH stress in E. faecalis OG1RF by conducting experimental evolution under acidic (pH 4.8), neutral pH (pH 7.0), and basic (pH 9.0) conditions. A serial planktonic culture was performed for 500 generations and in a high-pH biofilm culture for 4 serial bead transfers. Nearly all of the mutations led to nonsynonomous codons, indicating adaptive selection. All of the acid-adapted clones from the planktonic culture showed a mutation in fusA (encoding elongation factor G). The acid-adapted fusA mutants had a trade-off of decreased resistance to fusidic acid (fusidate). All of the base-adapted clones from the planktonic cultures as well as some from the biofilm-adapted cultures showed mutations that affected the Pst phosphate ABC transporter (pstA, pstB, pstB2, pstC) and pyrR (pyrimidine biosynthesis regulator/uracil phosphoribosyltransferase). The biofilm cultures produced small-size colonies on brain heart infusion agar. These variants each contained a single mutation in pstB2, pstC, or pyrR. The pst and pyrR mutants outgrew the ancestral strain at pH 9.2, with a trade-off of lower growth at pH 4.8. Additional genes that had a mutation in multiple clones that evolved at high pH (but not at low pH) include opp1BCDF (oligopeptide ABC transporter), ccpA (catabolite control protein A), and ftsZ (septation protein). Overall, the experimental evolution of E. faecalis showed a strong pH dependence, favoring the fusidate-sensitive elongation factor G modification at low pH and the loss of phosphate transport genes at high pH. IMPORTANCE E. faecalis bacteria are found in dental biofilms, where they experience low pH as a result of fermentative metabolism. Thus, the effect of pH on antibiotic resistance has clinical importance. The loss of fusidate resistance is notable for OG1RF strains in which fusidate resistance is assumed to be a stable genetic marker. In endodontal infections, enterococci can resist calcium hydroxide therapy that generates extremely high pH values. In other environments, such as the soil and plant rhizosphere, enterococci experience acidification that is associated with climate change. Thus, the pH modulation of natural selection in enterococci is important for human health as well as for understanding soil environments.
Collapse
Affiliation(s)
| | - Ayman Wadud
- Department of Biology, Kenyon College, Gambier, Ohio, USA
| | - Zachary Slimak
- Department of Biology, Kenyon College, Gambier, Ohio, USA
| | | |
Collapse
|
16
|
Wei Y, Sturges CI, Palmer KL. Human Serum Supplementation Promotes Streptococcus mitis Growth and Induces Specific Transcriptomic Responses. Microbiol Spectr 2023; 11:e0512922. [PMID: 37014220 PMCID: PMC10269507 DOI: 10.1128/spectrum.05129-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 03/01/2023] [Indexed: 04/05/2023] Open
Abstract
Streptococcus mitis is a normal member of the human oral microbiota and a leading opportunistic pathogen causing infective endocarditis (IE). Despite the complex interactions between S. mitis and the human host, understanding of S. mitis physiology and its mechanisms of adaptation to host-associated environments is inadequate, especially compared with other IE bacterial pathogens. This study reports the growth-promoting effects of human serum on S. mitis and other pathogenic streptococci, including S. oralis, S. pneumoniae, and S. agalactiae. Using transcriptomic analyses, we identified that, with the addition of human serum, S. mitis downregulates uptake systems for metal ions and sugars, fatty acid biosynthetic genes, and genes involved in stress response and other processes related with growth and replication. S. mitis upregulates uptake systems for amino acids and short peptides in response to human serum. Zinc availability and environmental signals sensed by the induced short peptide binding proteins were not sufficient to confer the growth-promoting effects. More investigation is required to establish the mechanism for growth promotion. Overall, our study contributes to the fundamental understanding of S. mitis physiology under host-associated conditions. IMPORTANCE S. mitis is exposed to human serum components during commensalism in the human mouth and bloodstream pathogenesis. However, the physiological effects of serum components on this bacterium remain unclear. Using transcriptomic analyses, S. mitis biological processes that respond to the presence of human serum were revealed, improving the fundamental understanding of S. mitis physiology in human host conditions.
Collapse
Affiliation(s)
- Yahan Wei
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas, USA
| | - Camille I. Sturges
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas, USA
| | - Kelli L. Palmer
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas, USA
| |
Collapse
|
17
|
Tymoszewska A, Szylińska M, Aleksandrzak-Piekarczyk T. The LiaFSR-LiaX System Mediates Resistance of Enterococcus faecium to Peptide Antibiotics and to Aureocin A53- and Enterocin L50-Like Bacteriocins. Microbiol Spectr 2023; 11:e0034323. [PMID: 37219451 PMCID: PMC10269926 DOI: 10.1128/spectrum.00343-23] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 05/07/2023] [Indexed: 05/24/2023] Open
Abstract
Multidrug-resistant Enterococcus faecium strains are currently a leading cause of difficult-to-treat nosocomial infections. The emerging resistance of enterococci to last-resort antibiotics, such as daptomycin, prompts a search for alternative antimicrobials. Aureocin A53- and enterocin L50-like bacteriocins are potent antimicrobial agents that form daptomycin-like cationic complexes and have a similar cell envelope-targeting mechanism of action, suggesting their potential as next-generation antibiotics. However, to ensure their safe use, the mechanisms of resistance to these bacteriocins and cross-resistance to antibiotics need to be well understood. Here, we investigated the genetic basis of E. faecium's resistance to aureocin A53- and enterocin L50-like bacteriocins and compared it with that to antibiotics. First, we selected spontaneous mutants resistant to the bacteriocin BHT-B and identified adaptive mutations in the liaFSR-liaX genes encoding the LiaFSR stress response regulatory system and the daptomycin-sensing protein LiaX, respectively. We then demonstrated that a gain-of-function mutation in liaR increases the expression of liaFSR, liaXYZ, cell wall remodeling-associated genes, and hypothetical genes involved in protection against various antimicrobials. Finally, we showed that adaptive mutations or overexpression of liaSR or liaR alone results in cross-resistance to other aureocin A53- and enterocin L50-like bacteriocins, as well as antibiotics targeting specific components of the cell envelope (daptomycin, ramoplanin, gramicidin) or ribosomes (kanamycin and gentamicin). Based on the obtained results, we concluded that activation of the LiaFSR-mediated stress response confers resistance to peptide antibiotics and bacteriocins via a cascade of reactions, eventually leading to cell envelope remodeling. IMPORTANCE Pathogenic enterococci carry virulence factors and a considerable resistome, which makes them one of the most serious and steadily increasing causes of hospital epidemiological risks. Accordingly, Enterococcus faecium is classified into a top-priority ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) group of six highly virulent and multidrug-resistant (MDR) bacterial pathogens for which novel antimicrobial agents need to be developed urgently. Alternative measures, such as the use of bacteriocins, separately or in combination with other antimicrobial agents (e.g., antibiotics), could be a potential solution, especially since several international health agencies recommend and support the development of such interventions. Nevertheless, in order to exploit their efficacy, more basic research on the mechanisms of cell killing and the development of resistance to bacteriocins is needed. The present study fills some of the knowledge gaps regarding the genetic basis of the development of resistance to potent antienterococcal bacteriocins, pointing out the common and divergent features regarding the cross-resistance to antibiotics.
Collapse
Affiliation(s)
- Aleksandra Tymoszewska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences (IBB PAS), Warsaw, Poland
| | - Marlena Szylińska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences (IBB PAS), Warsaw, Poland
| | | |
Collapse
|
18
|
Rao Tatta E, Paul S, Kumavath R. Transcriptome Analysis revealed the Synergism of Novel Rhodethrin inhibition on Biofilm architecture, Antibiotic Resistance and Quorum sensing inEnterococcus faecalis. Gene 2023; 871:147436. [PMID: 37075926 DOI: 10.1016/j.gene.2023.147436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 03/31/2023] [Accepted: 04/13/2023] [Indexed: 04/21/2023]
Abstract
Enterococcus sp. emerged as an opportunistic nosocomial pathogen with the highest antibiotic resistance and mortality rate. Biofilm is problematic primarily since it is regulated by the global bacterial cell to cell communication mediated by the quorum sensing system. sing system. Thus, potential natural antagonists in a novel drug formulation against biofilm-forming Enterococcus faecalis is critical. We used RNA-Seq to evaluate the effects of the novel molecule rhodethrin with chloramphenicol induced on Enterococcus faecalis and DEGs were identified. In transcriptome sequence analysis, a total of 448 with control Vs rhodethrin, 1591 were in control Vs chloramphenicol, 379 genes were DEGs from control Vs synergies, in rhodethrin with chloramphenicol, 379 genes were differentially expressed, whereas 264 genes were significantly downregulated, indicating that 69.69% ofE. faecaliswas altered. The transcriptional sequence data further expression analysis qRT-PCR, and the results shed that the expression profiles of five significant biofilm formation responsible genes such as, Ace, AtpB, lepA, bopD, and typA, 3 genes involved in quorum sensing are sylA, fsrC and camE, and 4 genes involved in resistance were among including liaX, typA, EfrA, and lepA, were significantly suppressed expressions of the biofilm, quorum sensing, and resistance that are supported by transcriptome analysis.
Collapse
Affiliation(s)
- Eswar Rao Tatta
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Tejaswini Hills, Periya (PO), Kasaragod, Kerala 671320, India
| | - Sayan Paul
- Department of Biochemistry & Molecular Biology, the University of Texas Medical Branch at Galveston, Galveston, Texas 77555, USA
| | - Ranjith Kumavath
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Tejaswini Hills, Periya (PO), Kasaragod, Kerala 671320, India; Department of Biotechnology, School of Life Sciences, Pondicherry University, Puducherry 605014, India.
| |
Collapse
|
19
|
Comparative Genome Analysis of Enterococcus cecorum Reveals Intercontinental Spread of a Lineage of Clinical Poultry Isolates. mSphere 2023; 8:e0049522. [PMID: 36794931 PMCID: PMC10117131 DOI: 10.1128/msphere.00495-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Enterococcus cecorum is an emerging pathogen responsible for osteomyelitis, spondylitis, and femoral head necrosis causing animal suffering and mortality and requiring antimicrobial use in poultry. Paradoxically, E. cecorum is a common inhabitant of the intestinal microbiota of adult chickens. Despite evidence suggesting the existence of clones with pathogenic potential, the genetic and phenotypic relatedness of disease-associated isolates remains little investigated. Here, we sequenced and analyzed the genomes and characterized the phenotypes of more than 100 isolates, the majority of which were collected over the last 10 years from 16 French broiler farms. Comparative genomics, genome-wide association studies, and the measured susceptibility to serum, biofilm-forming capacity, and adhesion to chicken type II collagen were used to identify features associated with clinical isolates. We found that none of the tested phenotypes could discriminate the origin of the isolates or the phylogenetic group. Instead, we found that most clinical isolates are grouped phylogenetically, and our analyses selected six genes that discriminate 94% of isolates associated with disease from those that are not. Analysis of the resistome and the mobilome revealed that multidrug-resistant clones of E. cecorum cluster into a few clades and that integrative conjugative elements and genomic islands are the main carriers of antimicrobial resistance. This comprehensive genomic analysis shows that disease-associated clones of E. cecorum belong mainly to one phylogenetic clade. IMPORTANCE Enterococcus cecorum is an important pathogen of poultry worldwide. It causes a number of locomotor disorders and septicemia, particularly in fast-growing broilers. Animal suffering, antimicrobial use, and associated economic losses require a better understanding of disease-associated E. cecorum isolates. To address this need, we performed whole-genome sequencing and analysis of a large collection of isolates responsible for outbreaks in France. By providing the first data set on the genetic diversity and resistome of E. cecorum strains circulating in France, we pinpoint an epidemic lineage that is probably also circulating elsewhere that should be targeted preferentially by preventive strategies in order to reduce the burden of E. cecorum-related diseases.
Collapse
|
20
|
Li G, Walker MJ, De Oliveira DMP. Vancomycin Resistance in Enterococcus and Staphylococcus aureus. Microorganisms 2022; 11:microorganisms11010024. [PMID: 36677316 PMCID: PMC9866002 DOI: 10.3390/microorganisms11010024] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/19/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022] Open
Abstract
Enterococcus faecalis, Enterococcus faecium and Staphylococcus aureus are both common commensals and major opportunistic human pathogens. In recent decades, these bacteria have acquired broad resistance to several major classes of antibiotics, including commonly employed glycopeptides. Exemplified by resistance to vancomycin, glycopeptide resistance is mediated through intrinsic gene mutations, and/or transferrable van resistance gene cassette-carrying mobile genetic elements. Here, this review will discuss the epidemiology of vancomycin-resistant Enterococcus and S. aureus in healthcare, community, and agricultural settings, explore vancomycin resistance in the context of van and non-van mediated resistance development and provide insights into alternative therapeutic approaches aimed at treating drug-resistant Enterococcus and S. aureus infections.
Collapse
|
21
|
Nguyen AH, Hood KS, Mileykovskaya E, Miller WR, Tran TT. Bacterial cell membranes and their role in daptomycin resistance: A review. Front Mol Biosci 2022; 9:1035574. [PMID: 36452455 PMCID: PMC9702088 DOI: 10.3389/fmolb.2022.1035574] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 10/26/2022] [Indexed: 11/16/2022] Open
Abstract
Lipids play a major role in bacterial cells. Foremost, lipids are the primary constituents of the cell membrane bilayer, providing structure and separating the cell from the surrounding environment. This makes the lipid bilayer a prime target for antimicrobial peptides and membrane-acting antibiotics such as daptomycin. In response, bacteria have evolved mechanisms by which the membrane can be adapted to resist attack by these antimicrobial compounds. In this review, we focus on the membrane phospholipid changes associated with daptomycin resistance in enterococci, Staphylococcus aureus, and the Viridans group streptococci.
Collapse
Affiliation(s)
- April H. Nguyen
- Center for Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, United States,Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, TX, United States
| | - Kara S. Hood
- Center for Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, United States,Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, TX, United States
| | - Eugenia Mileykovskaya
- Department of Biochemistry and Molecular Biology, McGovern Medical School, University of Texas Health Science Center, Houston, TX, United States
| | - William R. Miller
- Center for Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, United States,Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, TX, United States
| | - Truc T. Tran
- Center for Infectious Diseases Research, Houston Methodist Research Institute, Houston, TX, United States,Division of Infectious Diseases, Department of Medicine, Houston Methodist Hospital, Houston, TX, United States,*Correspondence: Truc T. Tran,
| |
Collapse
|
22
|
Liu E, Chen Y, Xu J, Gu S, An N, Xin J, Wang W, Liu Z, An Q, Yi J, Yin W. Platelets Inhibit Methicillin-Resistant Staphylococcus aureus by Inducing Hydroxyl Radical-Mediated Apoptosis-Like Cell Death. Microbiol Spectr 2022; 10:e0244121. [PMID: 35852345 PMCID: PMC9431477 DOI: 10.1128/spectrum.02441-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 05/19/2022] [Indexed: 11/20/2022] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common drug-resistant bacteria and poses a significant threat to human health. Due to the emergence of multidrug resistance, limited drugs are available for the treatment of MRSA infections. In recent years, platelets have been reported to play important roles in inflammation and immune responses, in addition to their functions in blood hemostasis and clotting. We and other researchers have previously reported that platelets can inhibit Staphylococcus aureus growth. However, it remained unclear whether platelets have the same antibacterial effect on drug-resistant strains. In this study, we hypothesized that platelets may also inhibit the growth of MRSA; the results confirmed that platelets significantly inhibited the growth of MRSA in vitro. In a murine model of MRSA infection, we found that a platelet transfusion alleviated the symptoms of MRSA infection; in contrast, depletion of platelets aggravated infective symptoms. Moreover, we observed an overproduction of hydroxyl radicals in MRSA following platelet treatment, which induced apoptosis-like death of MRSA. Our findings demonstrate that platelets can inhibit MRSA growth by promoting the overproduction of hydroxyl radicals and inducing apoptosis-like death. IMPORTANCE The widespread use of antibiotics has led to the emergence of drug-resistant bacteria, particularly multidrug-resistant bacteria. MRSA is the most common drug-resistant bacterium that causes suppurative infections in humans. As only a limited number of drugs are available to treat the infections caused by drug-resistant pathogens, it is imperative to develop novel and effective biological agents for treating MRSA infections. This is the first study to show that platelets can inhibit MRSA growth in vitro and in vivo. Our results revealed that platelets enhanced the production of hydroxyl radicals in MRSA, which induced a series of apoptosis hallmarks in MRSA, including DNA fragmentation, chromosome condensation, phosphatidylserine exposure, membrane potential depolarization, and increased intracellular caspase activity. These findings may further our understanding of platelet function.
Collapse
Affiliation(s)
- Erxiong Liu
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| | - Yutong Chen
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| | - Jinmei Xu
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| | - Shunli Gu
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| | - Ning An
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| | - Jiajia Xin
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| | - Wenting Wang
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| | - Zhixin Liu
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| | - Qunxing An
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| | - Jing Yi
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| | - Wen Yin
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi’an, Shanxi, China
| |
Collapse
|
23
|
Rosenbergová Z, Oftedal TF, Ovchinnikov KV, Thiyagarajah T, Rebroš M, Diep DB. Identification of a Novel Two-Peptide Lantibiotic from Vagococcus fluvialis. Microbiol Spectr 2022; 10:e0095422. [PMID: 35730941 PMCID: PMC9431498 DOI: 10.1128/spectrum.00954-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 05/24/2022] [Indexed: 11/20/2022] Open
Abstract
Infections caused by multiresistant pathogens have become a major problem in both human and veterinary medicine. Due to the declining efficacy of many antibiotics, new antimicrobials are needed. Promising alternatives or additions to antibiotics are bacteriocins, antimicrobial peptides of bacterial origin with activity against many pathogens, including antibiotic-resistant strains. From a sample of fermented maize, we isolated a Vagococcus fluvialis strain producing a bacteriocin with antimicrobial activity against multiresistant Enterococcus faecium. Whole-genome sequencing revealed the genes for a novel two-peptide lantibiotic. The production of the lantibiotic by the isolate was confirmed by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry, which revealed distinct peaks at 4,009.4 m/z and 3,181.7 m/z in separate fractions from reversed-phase chromatography. The combination of the two peptides resulted in a 1,200-fold increase in potency, confirming the two-peptide nature of the bacteriocin, named vagococcin T. The bacteriocin was demonstrated to kill sensitive cells by the formation of pores in the cell membrane, and its inhibition spectrum covers most Gram-positive bacteria, including multiresistant pathogens. To our knowledge, this is the first bacteriocin characterized from Vagococcus. IMPORTANCE Enterococci are common commensals in the intestines of humans and animals, but in recent years, they have been identified as one of the major causes of hospital-acquired infections due to their ability to quickly acquire virulence and antibiotic resistance determinants. Many hospital isolates are multiresistant, thereby making current therapeutic options critically limited. Novel antimicrobials or alternative therapeutic approaches are needed to overcome this global problem. Bacteriocins, natural ribosomally synthesized peptides produced by bacteria to eliminate other bacterial species living in a competitive environment, provide such an alternative. In this work, we purified and characterized a novel two-peptide lantibiotic produced by Vagococcus fluvialis LMGT 4216 isolated from fermented maize. The novel lantibiotic showed a broad spectrum of inhibition of Gram-positive strains, including vancomycin-resistant Enterococcus faecium, demonstrating its therapeutic potential.
Collapse
Affiliation(s)
- Zuzana Rosenbergová
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway
- Institute of Biotechnology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovakia
| | - Thomas F. Oftedal
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway
| | - Kirill V. Ovchinnikov
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway
| | - Thasanth Thiyagarajah
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway
| | - Martin Rebroš
- Institute of Biotechnology, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovakia
| | - Dzung B. Diep
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway
| |
Collapse
|
24
|
Antimicrobial tolerance and its role in the development of resistance: Lessons from enterococci. Adv Microb Physiol 2022; 81:25-65. [PMID: 36167442 DOI: 10.1016/bs.ampbs.2022.06.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Bacteria have developed resistance against every antimicrobial in clinical use at an alarming rate. There is a critical need for more effective use of antimicrobials to both extend their shelf life and prevent resistance from arising. Significantly, antimicrobial tolerance, i.e., the ability to survive but not proliferate during antimicrobial exposure, has been shown to precede the development of bona fide antimicrobial resistance (AMR), sparking a renewed and rapidly increasing interest in this field. As a consequence, problematic infections for the first time are now being investigated for antimicrobial tolerance, with increasing reports demonstrating in-host evolution of antimicrobial tolerance. Tolerance has been identified in a wide array of bacterial species to all bactericidal antimicrobials. Of particular interest are enterococci, which contain the opportunistic bacterial pathogens Enterococcus faecalis and Enterococcus faecium. Enterococci are one of the leading causes of hospital-acquired infection and possess intrinsic tolerance to a number of antimicrobial classes. Persistence of these infections in the clinic is of growing concern, particularly for the immunocompromised. Here, we review current known mechanisms of antimicrobial tolerance, and include an in-depth analysis of those identified in enterococci with implications for both the development and prevention of AMR.
Collapse
|
25
|
Adaptation of the gut pathobiont Enterococcus faecalis to deoxycholate and taurocholate bile acids. Sci Rep 2022; 12:8485. [PMID: 35590028 PMCID: PMC9120511 DOI: 10.1038/s41598-022-12552-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 05/11/2022] [Indexed: 11/24/2022] Open
Abstract
Enterococcus faecalis is a natural inhabitant of the human gastrointestinal tract. This bacterial species is subdominant in a healthy physiological state of the gut microbiota (eubiosis) in adults, but can become dominant and cause infections when the intestinal homeostasis is disrupted (dysbiosis). The relatively high concentrations of bile acids deoxycholate (DCA) and taurocholate (TCA) hallmark eubiosis and dysbiosis, respectively. This study aimed to better understand how E. faecalis adapts to DCA and TCA. We showed that DCA impairs E. faecalis growth and possibly imposes a continuous adjustment in the expression of many essential genes, including a majority of ribosomal proteins. This may account for slow growth and low levels of E. faecalis in the gut. In contrast, TCA had no detectable growth effect. The evolving transcriptome upon TCA adaptation showed the early activation of an oligopeptide permease system (opp2) followed by the adjustment of amino acid and nucleotide metabolisms. We provide evidence that TCA favors the exploitation of oligopeptide resources to fuel amino acid needs in limiting oligopeptide conditions. Altogether, our data suggest that the combined effects of decreased DCA and increased TCA concentrations can contribute to the rise of E. faecalis population during dysbiosis.
Collapse
|
26
|
Mechanism of cooperative N-glycan processing by the multi-modular endoglycosidase EndoE. Nat Commun 2022; 13:1137. [PMID: 35241669 PMCID: PMC8894350 DOI: 10.1038/s41467-022-28722-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 02/04/2022] [Indexed: 11/29/2022] Open
Abstract
Bacteria produce a remarkably diverse range of glycoside hydrolases to metabolize glycans from the environment as a primary source of nutrients, and to promote the colonization and infection of a host. Here we focus on EndoE, a multi-modular glycoside hydrolase secreted by Enterococcus faecalis, one of the leading causes of healthcare-associated infections. We provide X-ray crystal structures of EndoE, which show an architecture composed of four domains, including GH18 and GH20 glycoside hydrolases connected by two consecutive three α-helical bundles. We determine that the GH20 domain is an exo-β-1,2-N-acetylglucosaminidase, whereas the GH18 domain is an endo-β-1,4-N-acetylglucosaminidase that exclusively processes the central core of complex-type or high-mannose-type N-glycans. Both glycoside hydrolase domains act in a concerted manner to process diverse N-glycans on glycoproteins, including therapeutic IgG antibodies. EndoE combines two enzyme domains with distinct functions and glycan specificities to play a dual role in glycan metabolism and immune evasion. EndoE is a multi-domain glycoside hydrolase of the human pathogen Enterococcus faecalis. Here, the authors present crystal structures of EndoE and provide biochemical insights into the molecular basis of EndoE’s substrate specificity and catalytic mechanism.
Collapse
|
27
|
Gargis AS, Spicer LM, Kent AG, Zhu W, Campbell D, McAllister G, Ewing TO, Albrecht V, Stevens VA, Sheth M, Padilla J, Batra D, Johnson JK, Halpin AL, Rasheed JK, Elkins CA, Karlsson M, Lutgring JD. Sentinel Surveillance Reveals Emerging Daptomycin-Resistant ST736 Enterococcus faecium and Multiple Mechanisms of Linezolid Resistance in Enterococci in the United States. Front Microbiol 2022; 12:807398. [PMID: 35178041 PMCID: PMC8846945 DOI: 10.3389/fmicb.2021.807398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 12/09/2021] [Indexed: 01/09/2023] Open
Abstract
Enterococcus faecalis and faecium with resistance to daptomycin and/or linezolid are emerging globally. We present the genomic characterization of daptomycin- and linezolid-resistant E. faecalis and E. faecium surveillance isolates from the United States, 2013–2016. Daptomycin resistance was low among E. faecalis (2/364, 0.5%) and E. faecium (17/344, 5%). The majority (71%, 12/17) of daptomycin-resistant E. faecium isolates belonged to the emerging ST736 clone and contained mutations in liaFSR and cls previously associated with resistance. However, 1/2 E. faecalis and 3/17 E. faecium did not contain these mutations previously associated with daptomycin resistance. Linezolid resistance was rare among E. faecalis (1/364, 0.3%) and E. faecium (2/344, 0.6%). These two E. faecium isolates, one of which was also resistant to daptomycin and vancomycin, contained the 23S rRNA nucleotide mutation (G2576T) associated with linezolid resistance. Long-read sequencing revealed the linezolid-resistant E. faecalis isolate contained chromosomal- and plasmid-encoded copies of optrA. The chromosomal optrA was located on the recently described Tn6674 multiresistance transposon. The second copy of optrA was encoded on an ∼65 kb mosaic plasmid, with component regions sharing high sequence identity to optrA-encoding multiresistance plasmids of animal origin. The optrA-encoding plasmid contained open reading frames predicted to encode proteins associated with a pheromone-responsive plasmid transfer system, and filter mating experiments confirmed the plasmid was conjugative. Continued surveillance of enterococci is necessary to assess the prevalence and trends of daptomycin and linezolid resistance in the United States, characterize resistance mechanisms and how they transfer, and monitor for emerging sequence types associated with resistance.
Collapse
Affiliation(s)
- Amy S Gargis
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Lori M Spicer
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States.,Goldbelt C6, LLC, Chesapeake, VA, United States
| | - Alyssa G Kent
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States.,Goldbelt C6, LLC, Chesapeake, VA, United States
| | - Wenming Zhu
- Division of Tuberculosis Elimination, National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Davina Campbell
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Gillian McAllister
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Thomas O Ewing
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States.,Goldbelt C6, LLC, Chesapeake, VA, United States
| | - Valerie Albrecht
- Office of the Director, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Valerie A Stevens
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Mili Sheth
- Biotechnology Core Facility Branch, Division of Scientific Resources, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Jasmine Padilla
- Biotechnology Core Facility Branch, Division of Scientific Resources, Centers for Disease Control and Prevention, Atlanta, GA, United States.,ASRT Incorporated, Atlanta, GA, United States
| | - Dhwani Batra
- Biotechnology Core Facility Branch, Division of Scientific Resources, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - J Kristie Johnson
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Alison Laufer Halpin
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - J Kamile Rasheed
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Christopher A Elkins
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Maria Karlsson
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Joseph D Lutgring
- Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| |
Collapse
|
28
|
Li B, Zhang Y, Guo Q, He S, Fan J, Xu L, Zhang Z, Wu W, Chu H. Antibacterial peptide RP557 increases the antibiotic sensitivity of Mycobacterium abscessus by inhibiting biofilm formation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 807:151855. [PMID: 34813807 DOI: 10.1016/j.scitotenv.2021.151855] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/16/2021] [Accepted: 11/17/2021] [Indexed: 06/13/2023]
Abstract
Biofilm formation is an important factor for Mycobacterium abscessus to resist harsh environment and produce drug resistance. The anti-biofilm activity of a newly designed antibacterial peptide, RP557, was investigated. The effect of RP557 alone or in combination with several clinically effective antibiotics, including clarithromycin, amikacin, cefoxitin and imipenem, on M. abscessus growth in biofilms was determined. Microstructural changes in biofilms after RP557 treatment were observed by scanning electron microscope. The effect of RP557 on the viability of bacteria was determined by Syto9/PI staining and fluorescence microscopy. Finally, the potential mechanism of RP557 action on biofilm development was explored by transcriptome analysis. M. abscessus growing in biofilms showed increased resistance to antimicrobial drugs. RP557 alone exhibited only moderate anti-M. abscessus activity in vitro, but significantly increased the antibiotic sensitivity of M. abscessus in biofilms. The inhibitory effect of RP557 on biofilm formation was visualized by the scanning electron microscope; fluorescence staining demonstrated increased bacterial death in response to RP557 treatment. Furthermore, comparative analysis of transcriptomic data suggested RP557 may inhibit biofilm formation by down-regulating nitrogen and fatty acid metabolism, as well as peptidoglycan biosynthesis. As such, RP557 is a potential candidate to include in novel strategies to treat M. abscessus infections.
Collapse
Affiliation(s)
- Bing Li
- Department of Respiratory and Critical Care Medicine, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China
| | - Yongjie Zhang
- Department of Respiratory and Critical Care Medicine, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China; School of Medicine, Tongji University, Shanghai 200092, China
| | - Qi Guo
- Department of Respiratory and Critical Care Medicine, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China; School of Medicine, Tongji University, Shanghai 200092, China
| | - Siyuan He
- Department of Respiratory and Critical Care Medicine, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China; School of Medicine, Tongji University, Shanghai 200092, China
| | - Junsheng Fan
- Department of Respiratory and Critical Care Medicine, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China; School of Medicine, Tongji University, Shanghai 200092, China
| | - Liyun Xu
- Department of Respiratory and Critical Care Medicine, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China
| | - Zhemin Zhang
- Department of Respiratory and Critical Care Medicine, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China
| | - Wenye Wu
- Department of Respiratory and Critical Care Medicine, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China.
| | - Haiqing Chu
- Department of Respiratory and Critical Care Medicine, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China; Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China.
| |
Collapse
|
29
|
Miller LN, Blake MJ, Page EF, Castillo HB, Calhoun TR. Phosphate Ions Alter the Binding of Daptomycin to Living Bacterial Cell Surfaces. ACS Infect Dis 2021; 7:3088-3095. [PMID: 34605244 DOI: 10.1021/acsinfecdis.1c00397] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Advancements in antibiotic drug design are often hindered by missing information on how these small molecules interact with living cells. The antibiotic, daptomycin, has found clinical success and an emerging resistance, but a comprehensive picture of its mechanism of action has remained elusive. Using a surface-specific spectroscopy technique, second harmonic generation, we are able to quantitatively assess the binding of daptomycin to living cell membranes without the addition of exogenous labels. Our results reveal similar binding affinities for both Gram-positive and Gram-negative bacteria studied, including Escherichia coli. More importantly, we show that the presence of phosphate ions influences the binding of daptomycin to the Gram-positive bacterium Enterococcus faecalis. The role of environmental phosphate has not previously been considered in any proposed mechanism, and its implications are expected to be important in vivo.
Collapse
Affiliation(s)
- Lindsey N. Miller
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Marea J. Blake
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Eleanor F. Page
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Hannah B. Castillo
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Tessa R. Calhoun
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| |
Collapse
|
30
|
Kundra S, Lam LN, Kajfasz JK, Casella LG, Andersen MJ, Abranches J, Flores-Mireles AL, Lemos JA. c-di-AMP Is Essential for the Virulence of Enterococcus faecalis. Infect Immun 2021; 89:e0036521. [PMID: 34424750 PMCID: PMC8519298 DOI: 10.1128/iai.00365-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 08/11/2021] [Indexed: 12/12/2022] Open
Abstract
Second messenger nucleotides are produced by bacteria in response to environmental stimuli and play a major role in the regulation of processes associated with bacterial fitness, including but not limited to osmoregulation, envelope homeostasis, central metabolism, and biofilm formation. In this study, we uncovered the biological significance of c-di-AMP in the opportunistic pathogen Enterococcus faecalis by isolating and characterizing strains lacking genes responsible for c-di-AMP synthesis (cdaA) and degradation (dhhP and gdpP). Using complementary approaches, we demonstrated that either complete loss of c-di-AMP (ΔcdaA strain) or c-di-AMP accumulation (ΔdhhP, ΔgdpP, and ΔdhhP ΔgdpP strains) drastically impaired general cell fitness and virulence of E. faecalis. In particular, the ΔcdaA strain was highly sensitive to envelope-targeting antibiotics, was unable to multiply and quickly lost viability in human serum or urine ex vivo, and was virtually avirulent in an invertebrate (Galleria mellonella) and in two catheter-associated mouse infection models that recapitulate key aspects of enterococcal infections in humans. In addition to evidence linking these phenotypes to altered activity of metabolite and peptide transporters and inability to maintain osmobalance, we found that the attenuated virulence of the ΔcdaA strain also could be attributed to a defect in Ebp pilus production and activity that severely impaired biofilm formation under both in vitro and in vivo conditions. Collectively, these results demonstrate that c-di-AMP signaling is essential for E. faecalis pathogenesis and a desirable target for drug development.
Collapse
Affiliation(s)
- Shivani Kundra
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - Ling Ning Lam
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - Jessica K. Kajfasz
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - Leila G. Casella
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - Marissa J. Andersen
- Department of Biological Sciences, University of Norte Dame, Notre Dame, Indiana, USA
| | - Jacqueline Abranches
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| | - Ana L. Flores-Mireles
- Department of Biological Sciences, University of Norte Dame, Notre Dame, Indiana, USA
| | - José A. Lemos
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
| |
Collapse
|
31
|
Alternatives to Fight Vancomycin-Resistant Staphylococci and Enterococci. Antibiotics (Basel) 2021; 10:antibiotics10091116. [PMID: 34572698 PMCID: PMC8471638 DOI: 10.3390/antibiotics10091116] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 12/25/2022] Open
Abstract
Gram positive pathogens are a significant cause of healthcare-associated infections, with Staphylococci and Enterococci being the most prevalent ones. Vancomycin, a last resort glycopeptide, is used to fight these bacteria but the emergence of resistance against this drug leaves some patients with few therapeutic options. To counter this issue, new generations of antibiotics have been developed but resistance has already been reported. In this article, we review the strategies in place or in development to counter vancomycin-resistant pathogens. First, an overview of traditional antimicrobials already on the market or in the preclinical or clinical pipeline used individually or in combination is summarized. The second part focuses on the non-traditional antimicrobials, such as antimicrobial peptides, bacteriophages and nanoparticles. The conclusion is that there is hitherto no substitute equivalent to vancomycin. However, promising strategies based on drugs with multiple mechanisms of action and treatments based on bacteriophages possibly combined with conventional antibiotics are hoped to provide treatment options for vancomycin-resistant Gram-positive pathogens.
Collapse
|
32
|
Zhang R, Barreras Beltran IA, Ashford NK, Penewit K, Waalkes A, Holmes EA, Hines KM, Salipante SJ, Xu L, Werth BJ. Synergy Between Beta-Lactams and Lipo-, Glyco-, and Lipoglycopeptides, Is Independent of the Seesaw Effect in Methicillin-Resistant Staphylococcus aureus. Front Mol Biosci 2021; 8:688357. [PMID: 34646861 PMCID: PMC8503943 DOI: 10.3389/fmolb.2021.688357] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 08/20/2021] [Indexed: 12/22/2022] Open
Abstract
Methicillin-resistant S. aureus (MRSA) are resistant to beta-lactams, but synergistic activity between beta-lactams and glycopeptides/lipopeptides is common. Many have attributed this synergy to the beta-lactam-glycopeptide seesaw effect; however, this association has not been rigorously tested. The objective of this study was to determine whether the seesaw effect is necessary for synergy and to measure the impact of beta-lactam exposure on lipid metabolism. We selected for three isogenic strains with reduced susceptibility to vancomycin, daptomycin, and dalbavancin by serial passaging the MRSA strain N315. We used whole genome sequencing to identify genetic variants that emerged and tested for synergy between vancomycin, daptomycin, or dalbavancin in combination with 6 beta-lactams with variable affinity for staphylococcal penicillin binding proteins (PBPs), including nafcillin, meropenem, ceftriaxone, ceftaroline, cephalexin, and cefoxitin, using time-kills. We observed that the seesaw effect with each beta-lactam was variable and the emergence of the seesaw effect for a particular beta-lactam was not necessary for synergy between that beta-lactam and vancomycin, daptomycin, or dalbavancin. Synergy was more commonly observed with vancomycin and daptomycin based combinations than dalbavancin in time-kills. Among the beta-lactams, cefoxitin and nafcillin were the most likely to exhibit synergy using the concentrations tested, while cephalexin was the least likely to exhibit synergy. Synergy was more common among the resistant mutants than the parent strain. Interestingly N315-D1 and N315-DAL0.5 both had mutations in vraTSR and walKR despite their differences in the seesaw effect. Lipidomic analysis of all strains exposed to individual beta-lactams at subinhibitory concentrations suggested that in general, the abundance of cardiolipins (CLs) and most free fatty acids (FFAs) positively correlated with the presence of synergistic effects while abundance of phosphatidylglycerols (PGs) and lysylPGs mostly negatively correlated with synergistic effects. In conclusion, the beta-lactam-glycopeptide seesaw effect and beta-lactam-glycopeptide synergy are distinct phenomena. This suggests that the emergence of the seesaw effect may not have clinical importance in terms of predicting synergy. Further work is warranted to characterize strains that don't exhibit beta-lactam synergy to identify which strains should be targeted with combination therapy and which ones cannot and to further investigate the potential role of CLs in mediating synergy.
Collapse
Affiliation(s)
- Rutan Zhang
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA, United States
| | | | - Nathaniel K. Ashford
- Department of Pharmacy, School of Pharmacy, University of Washington, Seattle, WA, United States
| | - Kelsi Penewit
- Department of Laboratory Medicine and Pathology, School of Medicine, University of Washington, Seattle, WA, United States
| | - Adam Waalkes
- Department of Laboratory Medicine and Pathology, School of Medicine, University of Washington, Seattle, WA, United States
| | - Elizabeth A. Holmes
- Department of Laboratory Medicine and Pathology, School of Medicine, University of Washington, Seattle, WA, United States
| | - Kelly M. Hines
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA, United States
| | - Stephen J. Salipante
- Department of Laboratory Medicine and Pathology, School of Medicine, University of Washington, Seattle, WA, United States
| | - Libin Xu
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA, United States
| | - Brian J. Werth
- Department of Pharmacy, School of Pharmacy, University of Washington, Seattle, WA, United States
| |
Collapse
|
33
|
Ridyard KE, Overhage J. The Potential of Human Peptide LL-37 as an Antimicrobial and Anti-Biofilm Agent. Antibiotics (Basel) 2021; 10:antibiotics10060650. [PMID: 34072318 PMCID: PMC8227053 DOI: 10.3390/antibiotics10060650] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/20/2021] [Accepted: 05/25/2021] [Indexed: 02/06/2023] Open
Abstract
The rise in antimicrobial resistant bacteria threatens the current methods utilized to treat bacterial infections. The development of novel therapeutic agents is crucial in avoiding a post-antibiotic era and the associated deaths from antibiotic resistant pathogens. The human antimicrobial peptide LL-37 has been considered as a potential alternative to conventional antibiotics as it displays broad spectrum antibacterial and anti-biofilm activities as well as immunomodulatory functions. While LL-37 has shown promising results, it has yet to receive regulatory approval as a peptide antibiotic. Despite the strong antimicrobial properties, LL-37 has several limitations including high cost, lower activity in physiological environments, susceptibility to proteolytic degradation, and high toxicity to human cells. This review will discuss the challenges associated with making LL-37 into a viable antibiotic treatment option, with a focus on antimicrobial resistance and cross-resistance as well as adaptive responses to sub-inhibitory concentrations of the peptide. The possible methods to overcome these challenges, including immobilization techniques, LL-37 delivery systems, the development of LL-37 derivatives, and synergistic combinations will also be considered. Herein, we describe how combination therapy and structural modifications to the sequence, helicity, hydrophobicity, charge, and configuration of LL-37 could optimize the antimicrobial and anti-biofilm activities of LL-37 for future clinical use.
Collapse
|
34
|
Zeth K, Sancho-Vaello E. Structural Plasticity of LL-37 Indicates Elaborate Functional Adaptation Mechanisms to Bacterial Target Structures. Int J Mol Sci 2021; 22:ijms22105200. [PMID: 34068993 PMCID: PMC8156758 DOI: 10.3390/ijms22105200] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/28/2021] [Accepted: 05/12/2021] [Indexed: 11/16/2022] Open
Abstract
The human cathelicidin LL-37 is a multifunctional peptide of the human innate immune system. Among the various functions of LL-37, its antimicrobial activity is important in controlling the microorganisms of the human body. The target molecules of LL-37 in bacteria include membrane lipids, lipopolysaccharides (LPS), lipoteichoic acid (LTA), proteins, DNA and RNA. In this mini-review, we summarize the entity of LL-37 structural data determined over the last 15 years and specifically discuss features implicated in the interactions with lipid-like molecules. For this purpose, we discuss partial and full-length structures of LL-37 determined in the presence of membrane-mimicking detergents. This constantly growing structural database is now composed of monomers, dimers, tetramers, and fiber-like structures. The diversity of these structures underlines an unexpected plasticity and highlights the conformational and oligomeric adaptability of LL-37 necessary to target different molecular scaffolds. The recent co-crystal structures of LL-37 in complex with detergents are particularly useful to understand how these molecules mimic lipids and LPS to induce oligomerization and fibrillation. Defined detergent binding sites provide deep insights into a new class of peptide scaffolds, widening our view on the fascinating world of the LL-37 structural factotum. Together, the new structures in their evolutionary context allow for the assignment of functionally conserved residues in oligomerization and target interactions. Conserved phenylalanine and arginine residues primarily mediate those interactions with lipids and LPS. The interactions with macromolecules such as proteins or DNA remain largely unexplored and open a field for future studies aimed at structures of LL-37 complexes. These complexes will then allow for the structure-based rational design of LL-37-derived peptides with improved antibiotic properties.
Collapse
Affiliation(s)
- Kornelius Zeth
- Department of Science and Environment, Roskilde University, Universitetsvej 1, 4000 Roskilde, Denmark
- Correspondence: (K.Z.); (E.S.-V.); Tel.: +45-604-666-29 (K.Z.)
| | - Enea Sancho-Vaello
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
- Correspondence: (K.Z.); (E.S.-V.); Tel.: +45-604-666-29 (K.Z.)
| |
Collapse
|
35
|
Wei L, Li M, Xia F, Wang J, Ran S, Huang Z, Liang J. Phosphate transport system mediates the resistance of Enterococcus faecalis to multidrug. Microbiol Res 2021; 249:126772. [PMID: 33930841 DOI: 10.1016/j.micres.2021.126772] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 03/04/2021] [Accepted: 04/20/2021] [Indexed: 01/12/2023]
Abstract
Enterococcus faecalis, a severe nosocomial and community opportunistic pathogen, is difficult to control due to its multidrug resistance. Through heredity and the recombination of intrinsic resistance genes and horizontally acquired resistance genes, E. faecalis can rapidly evolve drug resistance. Nisin, an important antimicrobial peptide, is extensively employed in the healthcare and food industries to inhibit Gram-positive bacteria and may induce the emergence of nisin-resistant bacteria worldwide. However, the mechanism governing nisin resistance in E. faecalis has not been fully elucidated. This study utilizes transposon insertion sequencing (TIS) to comprehensively explore novel genes related to nisin resistance. According to the analysis of TIS results, hundreds of genes appear to be essential for nisin resistance in E. faecalis. The phosphate transport system (OG1RF_10018-10021, named PTS), which is screened by TIS results, enhances the resistance of E. faecalis to nisin, the mechanism of which may be involved in potA and/or OG1RF_10526 (hypothetical gene). Meanwhile, PTS also strongly represses the biosynthesis of ribosomes to increase the sensitivity of E. faecalis to gentamycin. In addition, the overexpression of PTS increases the sensitivity of E. faecalis to daptomycin, the mechanism of which is independent of the LiaFSR system. This study first demonstrated that E. faecalis utilizes PTS to mediate the resistance to multidrug, which may help to elucidate the mechanism governing drug resistance and to establish guidelines for the treatment of infectious diseases caused by E. faecalis.
Collapse
Affiliation(s)
- Lifan Wei
- Department of Endodontics and Operative Dentistry, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Oral Diseases, Shanghai, China; Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, China
| | - Mingwei Li
- Department of Pediatric Dentistry, Nanjing Stomatological Hospital, Medical School of Nanjing University, 30 Zhongyang Road, Nanjing, 210008, China
| | - Feng Xia
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Jia Wang
- Department of Endodontics and Operative Dentistry, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Oral Diseases, Shanghai, China; Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, China
| | - Shujun Ran
- Department of Endodontics and Operative Dentistry, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Oral Diseases, Shanghai, China; Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, China
| | - Zhengwei Huang
- Department of Endodontics and Operative Dentistry, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Oral Diseases, Shanghai, China; Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, China
| | - Jingping Liang
- Department of Endodontics and Operative Dentistry, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Oral Diseases, Shanghai, China; Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, China.
| |
Collapse
|
36
|
Liu Y, Liu Y, Liu Z, Hill JP, Alowasheeir A, Xu Z, Xu X, Yamauchi Y. Ultra-durable, multi-template molecularly imprinted polymers for ultrasensitive monitoring and multicomponent quantification of trace sulfa antibiotics. J Mater Chem B 2021; 9:3192-3199. [PMID: 33885623 DOI: 10.1039/d1tb00091h] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Traditional analysis methods are susceptible to interference caused by the complexity of sample matrices, and detector surface fouling arising from nonspecific adsorption of microorganisms (in biological samples) which leads in particular to a gradual loss of sensitivity. Imprinted materials can be used to effectively reduce interference originating in the matrices. However, the poor reproducibility and multicomponent quantification of trace antibiotics represent significant challenges to the detection process. Meanwhile, the high biological risk presented by bacterial antibiotic immunity and the persistence of antibiotics in foodstuffs, especially meat, both caused by the overuse of sulfonamide antibiotics, remain urgent issues. Here, we present the first example of a method for the accurate quantification of trace sulfa antibiotics (SAs) based on multi-template imprinted polymers (MMIPs). Levels of multiple SAs have been simultaneously successfully quantified by applying MMIP extraction coupled with UPLC-MS/MS analysis. This method shows excellent linearity of detection in the range of 0.1-500 μg L-1, and ultrasensitivity with low limits of detection of 0.03 μg L-1. The maximum SA residue recovered from sample tissues by using MMIPs was 5.48 μg g-1. MMIP-coupled UPLC-MS/MS quantification of SAs is an accurate and repeatable method for the monitoring of SA accumulation in mouse tissue samples. It also provides an effective strategy for the tracking and quantification of drugs in other biological samples.
Collapse
Affiliation(s)
- Yuanchen Liu
- Faculty of Science, Kunming University of Science and Technology, Kunming 650500, China.
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Sun Q, Duan M, Fan W, Fan B. Ca-Si mesoporous nanoparticles with the optimal Ag-Zn ratio inhibit the Enterococcus faecalis infection of teeth through dentinal tubule infiltration: an in vitro and in vivo study. J Mater Chem B 2021; 9:2200-2211. [PMID: 33447835 DOI: 10.1039/d0tb02704a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Enterococcus faecalis is the main cause of refractory root canal infections in human teeth. The control of root canal infection is one of the conditions necessary for the successful treatment of refractory root canal infections. In the present study, nano-scale silver-zinc-calcium-silica particles loaded with different ratios of silver-zinc were successfully prepared (Ag0.5Zn3-MCSNs and Ag0.5Zn10-MCSNs). The release profiles, antibacterial activity against E. faecalis, infiltration depth into dentinal tubules, biocompatibility and effects on dentin microhardness in vitro were investigated. In addition, the antimicrobial effects of the particles against Enterococcus faecalis reinfection were evaluated in vivo in the teeth of beagle dogs. Ag, Zn, Ca and Si were released from Ag-Zn-MCSNs, and the atomic ratio of silver and zinc released can reach the optimal value of 1 : 12 (Ag0.5Zn10-MCSNs). The particles also showed good biocompatibility and antibacterial activity against Enterococcus faecalis and did not reduce the hardness of dentin. The nanoparticles could be driven into the dentinal tubules of dentin slices by ultrasonic activation. In the root canals of beagle dogs, both Ag0.5Zn3-MCSNs and Ag0.5Zn10-MCSNs demonstrated strong preventive effects against E. faecalis infection. The Ag-Zn-Ca-Si mesoporous nanoparticles may develop into a new effective root canal disinfectant or root canal sealer.
Collapse
Affiliation(s)
- Qing Sun
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, People's Republic of China.
| | - Mengting Duan
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, People's Republic of China.
| | - Wei Fan
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, People's Republic of China.
| | - Bing Fan
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, People's Republic of China.
| |
Collapse
|
38
|
Abstract
Serious infections owing to vancomycin-resistant enterococci have historically proven to be difficult clinical cases, requiring combination therapy and management of treatment-related toxicity. Despite the introduction of new antibiotics with activity against vancomycin-resistant enterococci to the therapeutic armamentarium, significant challenges remain. An understanding of the factors driving the emergence of resistance in vancomycin-resistant enterococci, the dynamics of gastrointestinal colonization and microbiota-mediated colonization resistance, and the mechanisms of resistance to the currently available therapeutics will permit clinicians to be better prepared to tackle these challenging hospital-associated pathogens.
Collapse
Affiliation(s)
- William R Miller
- Department of Internal Medicine, Division of Infectious Diseases, University of Texas Health Science Center at Houston, McGovern Medical School, 6431 Fannin St. MSB 2.112, Houston, TX 77030, USA; Center for Antimicrobial Resistance and Microbial Genomics (CARMiG)
| | - Barbara E Murray
- Department of Internal Medicine, Division of Infectious Diseases, University of Texas Health Science Center at Houston, McGovern Medical School, 6431 Fannin St. MSB 2.112, Houston, TX 77030, USA; Center for Antimicrobial Resistance and Microbial Genomics (CARMiG); Department of Microbiology and Molecular Genetics, 6431 Fannin St. MSB 2.112, Houston, TX 77030, USA
| | - Louis B Rice
- Department of Internal Medicine, Brown University, 593 Eddy Street, Providence, RI 02903, USA
| | - Cesar A Arias
- Department of Internal Medicine, Division of Infectious Diseases, University of Texas Health Science Center at Houston, McGovern Medical School, 6431 Fannin St. MSB 2.112, Houston, TX 77030, USA; Center for Antimicrobial Resistance and Microbial Genomics (CARMiG); Department of Microbiology and Molecular Genetics, 6431 Fannin St. MSB 2.112, Houston, TX 77030, USA; University of Texas Health Science Center at Houston, School of Public Health, Houston, TX, USA; Molecular Genetics and Antimicrobial Resistance Unit, International Center for Microbial Genomics, Universidad El Bosque, Bogota, Colombia.
| |
Collapse
|
39
|
Genes Contributing to the Unique Biology and Intrinsic Antibiotic Resistance of Enterococcus faecalis. mBio 2020; 11:mBio.02962-20. [PMID: 33234689 PMCID: PMC7701990 DOI: 10.1128/mbio.02962-20] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Enterococci are leading causes of antibiotic-resistant infection transmitted in hospitals. The intrinsic hardiness of these organisms allows them to survive disinfection practices and then proliferate in the gastrointestinal tracts of antibiotic-treated patients. The objective of this study was to identify the underlying genetic basis for its unusual hardiness. Using a functional genomic approach, we identified traits and pathways of general importance for enterococcal survival and growth that distinguish them from closely related pathogens as well as ancestrally related species. We further identified unique traits that enable them to survive antibiotic challenge, revealing a large set of genes that contribute to intrinsic antibiotic resistance and a smaller set of uniquely important genes that are rare outside enterococci. The enterococci, which are among the leading causes of multidrug-resistant (MDR) hospital infection, are notable for their environmental ruggedness, which extends to intrinsic antibiotic resistance. To identify genes that confer this unique property, we used Tn-seq to comprehensively explore the genome of MDR Enterococcus faecalis strain MMH594 for genes important for growth in nutrient-containing medium and with low-level antibiotic challenge. As expected, a large core of genes for DNA replication, expression, and central metabolism, shared with other bacteria, are intolerant to transposon disruption. However, genes were identified that are important to E. faecalis that are either absent from or unimportant for Staphylococcus aureus and Streptococcus pneumoniae fitness when similarly tested. Further, 217 genes were identified that when challenged by sub-MIC antibiotic levels exhibited reduced tolerance to transposon disruption, including those previously shown to contribute to intrinsic resistance, and others not previously ascribed this role. E. faecalis is one of the few Gram-positive bacteria experimentally shown to possess a functional Entner-Doudoroff pathway for carbon metabolism, a pathway that contributes to stress tolerance in other microbes. Through functional genomics and network analysis we defined the unusual structure of this pathway in E. faecalis and assessed its importance. These approaches also identified toxin-antitoxin and related systems that are unique and active in E. faecalis. Finally, we identified genes that are absent in the closest nonenterococcal relatives, the vagococci, and that contribute importantly to fitness with and without antibiotic selection, advancing an understanding of the unique biology of enterococci.
Collapse
|
40
|
Assoni L, Milani B, Carvalho MR, Nepomuceno LN, Waz NT, Guerra MES, Converso TR, Darrieux M. Resistance Mechanisms to Antimicrobial Peptides in Gram-Positive Bacteria. Front Microbiol 2020; 11:593215. [PMID: 33193264 PMCID: PMC7609970 DOI: 10.3389/fmicb.2020.593215] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 09/03/2020] [Indexed: 02/06/2023] Open
Abstract
With the alarming increase of infections caused by pathogenic multidrug-resistant bacteria over the last decades, antimicrobial peptides (AMPs) have been investigated as a potential treatment for those infections, directly through their lytic effect or indirectly, due to their ability to modulate the immune system. There are still concerns regarding the use of such molecules in the treatment of infections, such as cell toxicity and host factors that lead to peptide inhibition. To overcome these limitations, different approaches like peptide modification to reduce toxicity and peptide combinations to improve therapeutic efficacy are being tested. Human defense peptides consist of an important part of the innate immune system, against a myriad of potential aggressors, which have in turn developed different ways to overcome the AMPs microbicidal activities. Since the antimicrobial activity of AMPs vary between Gram-positive and Gram-negative species, so do the bacterial resistance arsenal. This review discusses the mechanisms exploited by Gram-positive bacteria to circumvent killing by antimicrobial peptides. Specifically, the most clinically relevant genera, Streptococcus spp., Staphylococcus spp., Enterococcus spp. and Gram-positive bacilli, have been explored.
Collapse
Affiliation(s)
- Lucas Assoni
- Laboratório de Biologia Molecular de Microrganismos, Universidade São Francisco, Bragança Paulista, Brazil
| | - Barbara Milani
- Laboratório de Biologia Molecular de Microrganismos, Universidade São Francisco, Bragança Paulista, Brazil
| | - Marianna Ribeiro Carvalho
- Laboratório de Biologia Molecular de Microrganismos, Universidade São Francisco, Bragança Paulista, Brazil
| | - Lucas Natanael Nepomuceno
- Laboratório de Biologia Molecular de Microrganismos, Universidade São Francisco, Bragança Paulista, Brazil
| | - Natalha Tedeschi Waz
- Laboratório de Biologia Molecular de Microrganismos, Universidade São Francisco, Bragança Paulista, Brazil
| | - Maria Eduarda Souza Guerra
- Laboratório de Biologia Molecular de Microrganismos, Universidade São Francisco, Bragança Paulista, Brazil
| | - Thiago Rojas Converso
- Laboratório de Biologia Molecular de Microrganismos, Universidade São Francisco, Bragança Paulista, Brazil
| | - Michelle Darrieux
- Laboratório de Biologia Molecular de Microrganismos, Universidade São Francisco, Bragança Paulista, Brazil
| |
Collapse
|
41
|
Kebriaei R, Stamper KC, Singh KV, Khan A, Rice SA, Dinh AQ, Tran TT, Murray BE, Arias CA, Rybak MJ. Mechanistic Insights Into the Differential Efficacy of Daptomycin Plus β-Lactam Combinations Against Daptomycin-Resistant Enterococcus faecium. J Infect Dis 2020; 222:1531-1539. [PMID: 32514561 PMCID: PMC7529040 DOI: 10.1093/infdis/jiaa319] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 06/02/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The combination of daptomycin (DAP) plus ampicillin (AMP), ertapenem (ERT), or ceftaroline has been demonstrated to be efficacious against a DAP-tolerant Enterococcus faecium strain (HOU503). However, the mechanism for the efficacy of these combinations against DAP-resistant (DAP-R) E. faecium strains is unknown. METHODS We investigated the efficacy of DAP in combination with AMP, ERT, ceftaroline, ceftriaxone, or amoxicillin against DAP-R E. faecium R497 using established in vitro and in vivo models. We evaluated pbp expression, levels of penicillin-binding protein (PBP) 5 (PBP5) and β-lactam binding affinity in HOU503 versus R497. RESULTS DAP plus AMP was the only efficacious regimen against DAP-R R497 and prevented emergence of resistance. DAP at 8, 6, and 4 mg/kg in combination with AMP was efficacious but showed delayed killing compared with 10 mg/kg. PBP5 of HOU503 exhibited amino acid substitutions in the penicillin-binding domain relative to R497. No difference in pbp mRNA or PBP5 levels was detected between HOU503 and R497. labeling of PBPs with Bocillin FL, a fluorescent penicillin derivative, showed increased β-lactam binding affinity of PBP5 of HOU503 compared with that of R497. CONCLUSIONS Only DAP (10 mg/kg) plus AMP or amoxicillin was efficacious against a DAP-R E. faecium strain, and pbp5 alleles may be important contributors to efficacy of DAP plus β-lactam therapy.
Collapse
Affiliation(s)
- Razieh Kebriaei
- Anti-Infective Research Laboratory, Eugene Applebaum College of Pharmacy & Health Sciences, Detroit, Michigan, USA
| | - Kyle C Stamper
- Anti-Infective Research Laboratory, Eugene Applebaum College of Pharmacy & Health Sciences, Detroit, Michigan, USA
| | - Kavindra V Singh
- Division of Infectious Diseases, UTHealth McGovern Medical School, Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, UTHealth McGovern Medical School, Houston, Texas, USA
| | - Ayesha Khan
- Division of Infectious Diseases, UTHealth McGovern Medical School, Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, UTHealth McGovern Medical School, Houston, Texas, USA
- Department of Microbiology and Molecular Genetics, UTHealth McGovern Medical School, Houston, Texas, USA
| | - Seth A Rice
- Anti-Infective Research Laboratory, Eugene Applebaum College of Pharmacy & Health Sciences, Detroit, Michigan, USA
| | - An Q Dinh
- Division of Infectious Diseases, UTHealth McGovern Medical School, Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, UTHealth McGovern Medical School, Houston, Texas, USA
| | - Truc T Tran
- Division of Infectious Diseases, UTHealth McGovern Medical School, Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, UTHealth McGovern Medical School, Houston, Texas, USA
| | - Barbara E Murray
- Division of Infectious Diseases, UTHealth McGovern Medical School, Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, UTHealth McGovern Medical School, Houston, Texas, USA
- Department of Microbiology and Molecular Genetics, UTHealth McGovern Medical School, Houston, Texas, USA
| | - Cesar A Arias
- Division of Infectious Diseases, UTHealth McGovern Medical School, Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, UTHealth McGovern Medical School, Houston, Texas, USA
- Department of Microbiology and Molecular Genetics, UTHealth McGovern Medical School, Houston, Texas, USA
- Center for Infectious Diseases, UTHealth School of Public Health, Houston, Texas, USA
- Molecular Genetics and Antimicrobial Resistance Unit, International Center for Microbial Genomics; Universidad El Bosque, Bogotá, Colombia
| | - Michael J Rybak
- Anti-Infective Research Laboratory, Eugene Applebaum College of Pharmacy & Health Sciences, Detroit, Michigan, USA
- School of Medicine, Wayne State University, Detroit, Michigan, USA
| |
Collapse
|
42
|
Ota Y, Furuhashi K, Hayashi W, Hirai N, Ishikawa J, Nagura O, Yamanaka K, Katahashi K, Aoki K, Nagano N, Maekawa M. Daptomycin resistant Enterococcus faecalis has a mutation in liaX, which encodes a surface protein that inhibits the LiaFSR systems and cell membrane remodeling. J Infect Chemother 2020; 27:90-93. [PMID: 32972829 DOI: 10.1016/j.jiac.2020.09.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/16/2020] [Accepted: 09/01/2020] [Indexed: 10/23/2022]
Abstract
The emergence of daptomycin (DAP) resistant Enterococcus species has increased worldwide, but the mechanisms for DAP resistance are not fully understood. We report a case of DAP resistant Enterococcus faecalis, from a clinical sample of a patient with diabetic ulcers, after DAP therapy. Whole-genome sequencing analysis revealed that the isolate had a loss-of-function point mutation within liaX encoding DAP-sensing surface protein, which inhibits the LiaFSR systems and cell membrane remodeling. This is the first case report of a clinical DAP resistant E. faecalis with a mutation in liaX.
Collapse
Affiliation(s)
- Yusuke Ota
- Department of Laboratory Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan.
| | - Kazuki Furuhashi
- Department of Laboratory Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan.
| | - Wataru Hayashi
- Department of Medical Sciences, Shinshu University Graduate School of Medicine, Science and Technology, Nagano, Japan.
| | - Nachi Hirai
- Department of Laboratory Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan.
| | - Jinko Ishikawa
- Department of Laboratory Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan.
| | - Osanori Nagura
- Department of Laboratory Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan.
| | - Katsumasa Yamanaka
- Department of Laboratory Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan.
| | - Kazuto Katahashi
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan.
| | - Kotaro Aoki
- Department of Microbiology and Infectious Diseases, Toho University School of Medicine, Tokyo, Japan.
| | - Noriyuki Nagano
- Department of Medical Sciences, Shinshu University Graduate School of Medicine, Science and Technology, Nagano, Japan.
| | - Masato Maekawa
- Department of Laboratory Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan.
| |
Collapse
|
43
|
Kmeck A, Tancer RJ, Ventura CR, Wiedman GR. Synergies with and Resistance to Membrane-Active Peptides. Antibiotics (Basel) 2020; 9:antibiotics9090620. [PMID: 32961656 PMCID: PMC7559582 DOI: 10.3390/antibiotics9090620] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/07/2020] [Accepted: 09/17/2020] [Indexed: 12/12/2022] Open
Abstract
Membrane-active peptides (MAPs) have long been thought of as the key to defeating antimicrobial-resistant microorganisms. Such peptides, however, may not be sufficient alone. In this review, we seek to highlight some of the common pathways for resistance, as well as some avenues for potential synergy. This discussion takes place considering resistance, and/or synergy in the extracellular space, at the membrane, and during interaction, and/or removal. Overall, this review shows that researchers require improved definitions of resistance and a more thorough understanding of MAP-resistance mechanisms. The solution to combating resistance may ultimately come from an understanding of how to harness the power of synergistic drug combinations.
Collapse
|
44
|
ExPortal and the LiaFSR Regulatory System Coordinate the Response to Cell Membrane Stress in Streptococcus pyogenes. mBio 2020; 11:mBio.01804-20. [PMID: 32934083 PMCID: PMC7492735 DOI: 10.1128/mbio.01804-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Bacterial two-component systems sense and induce transcriptional changes in response to environmental stressors, including antimicrobials and human antimicrobial peptides. Since the stresses imposed by the host’s defensive responses may act as markers of specific temporal stages of disease progression or host compartments, pathogens often coordinately regulate stress response programs with virulence factor expression. The mechanism by which bacteria recognize these stresses and subsequently induce transcriptional responses remains not well understood. In this study, we showed that LiaFSR senses cell envelope stress through colocalization of LiaF and LiaS with the group A Streptococcus (GAS) ExPortal and is activated in direct response to ExPortal disruption by antimicrobials or human antimicrobial peptides. Our studies shed new light on the sensing of cell envelope stress in Gram-positive bacteria and may contribute to the development of therapies targeting these processes. LiaFSR is a gene regulatory system important for response to cell membrane stress in Gram-positive bacteria but is minimally studied in the important human pathogen group A Streptococcus (GAS). Using immunofluorescence and immunogold electron microscopy, we discovered that LiaF (a membrane-bound repressor protein) and LiaS (a sensor kinase) reside within the GAS membrane microdomain (ExPortal). Cell envelope stress induced by antimicrobials resulted in ExPortal disruption and activation of the LiaFSR system. The only human antimicrobial peptide whose presence resulted in ExPortal disruption and LiaFSR activation was the alpha-defensin human neutrophil peptide 1 (hNP-1). Elimination of membrane cardiolipin through targeted gene deletion resulted in loss of LiaS colocalization with the GAS ExPortal and activation of LiaFSR, whereas LiaF membrane localization was unaffected. Isogenic mutants lacking either LiaF or LiaS revealed a critical role of LiaF in ExPortal integrity. Thus, LiaF and LiaS colocalize with the GAS ExPortal by distinct mechanisms, further supporting codependence. These are the first data identifying a multicomponent signal system within the ExPortal, thereby providing new insight into bacterial intramembrane signaling in GAS that may serve as a paradigm for Gram-positive bacteria.
Collapse
|
45
|
Karas JA, Carter GP, Howden BP, Turner AM, Paulin OKA, Swarbrick JD, Baker MA, Li J, Velkov T. Structure–Activity Relationships of Daptomycin Lipopeptides. J Med Chem 2020; 63:13266-13290. [DOI: 10.1021/acs.jmedchem.0c00780] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- John A. Karas
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Glen P. Carter
- Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Benjamin P. Howden
- Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Adrianna M. Turner
- Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Olivia K. A. Paulin
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - James D. Swarbrick
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Mark. A. Baker
- Priority Research Centre in Reproductive Science, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Jian Li
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Tony Velkov
- Department of Pharmacology & Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
| |
Collapse
|
46
|
Fodor A, Abate BA, Deák P, Fodor L, Gyenge E, Klein MG, Koncz Z, Muvevi J, Ötvös L, Székely G, Vozik D, Makrai L. Multidrug Resistance (MDR) and Collateral Sensitivity in Bacteria, with Special Attention to Genetic and Evolutionary Aspects and to the Perspectives of Antimicrobial Peptides-A Review. Pathogens 2020; 9:pathogens9070522. [PMID: 32610480 PMCID: PMC7399985 DOI: 10.3390/pathogens9070522] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 06/23/2020] [Accepted: 06/23/2020] [Indexed: 12/18/2022] Open
Abstract
Antibiotic poly-resistance (multidrug-, extreme-, and pan-drug resistance) is controlled by adaptive evolution. Darwinian and Lamarckian interpretations of resistance evolution are discussed. Arguments for, and against, pessimistic forecasts on a fatal “post-antibiotic era” are evaluated. In commensal niches, the appearance of a new antibiotic resistance often reduces fitness, but compensatory mutations may counteract this tendency. The appearance of new antibiotic resistance is frequently accompanied by a collateral sensitivity to other resistances. Organisms with an expanding open pan-genome, such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae, can withstand an increased number of resistances by exploiting their evolutionary plasticity and disseminating clonally or poly-clonally. Multidrug-resistant pathogen clones can become predominant under antibiotic stress conditions but, under the influence of negative frequency-dependent selection, are prevented from rising to dominance in a population in a commensal niche. Antimicrobial peptides have a great potential to combat multidrug resistance, since antibiotic-resistant bacteria have shown a high frequency of collateral sensitivity to antimicrobial peptides. In addition, the mobility patterns of antibiotic resistance, and antimicrobial peptide resistance, genes are completely different. The integron trade in commensal niches is fortunately limited by the species-specificity of resistance genes. Hence, we theorize that the suggested post-antibiotic era has not yet come, and indeed might never come.
Collapse
Affiliation(s)
- András Fodor
- Department of Genetics, University of Szeged, H-6726 Szeged, Hungary;
- Correspondence: or (A.F.); (L.M.); Tel.: +36-(30)-490-9294 (A.F.); +36-(30)-271-2513 (L.M.)
| | - Birhan Addisie Abate
- Ethiopian Biotechnology Institute, Agricultural Biotechnology Directorate, Addis Ababa 5954, Ethiopia;
| | - Péter Deák
- Department of Genetics, University of Szeged, H-6726 Szeged, Hungary;
- Institute of Biochemistry, Biological Research Centre, H-6726 Szeged, Hungary
| | - László Fodor
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, P.O. Box 22, H-1581 Budapest, Hungary;
| | - Ervin Gyenge
- Hungarian Department of Biology and Ecology, Faculty of Biology and Geology, Babeș-Bolyai University, 5-7 Clinicilor St., 400006 Cluj-Napoca, Romania; (E.G.); (G.S.)
- Institute for Research-Development-Innovation in Applied Natural Sciences, Babeș-Bolyai University, 30 Fântânele St., 400294 Cluj-Napoca, Romania
| | - Michael G. Klein
- Department of Entomology, The Ohio State University, 1680 Madison Ave., Wooster, OH 44691, USA;
| | - Zsuzsanna Koncz
- Max-Planck Institut für Pflanzenzüchtungsforschung, Carl-von-Linné-Weg 10, D-50829 Köln, Germany;
| | | | - László Ötvös
- OLPE, LLC, Audubon, PA 19403-1965, USA;
- Institute of Medical Microbiology, Semmelweis University, H-1085 Budapest, Hungary
- Arrevus, Inc., Raleigh, NC 27612, USA
| | - Gyöngyi Székely
- Hungarian Department of Biology and Ecology, Faculty of Biology and Geology, Babeș-Bolyai University, 5-7 Clinicilor St., 400006 Cluj-Napoca, Romania; (E.G.); (G.S.)
- Institute for Research-Development-Innovation in Applied Natural Sciences, Babeș-Bolyai University, 30 Fântânele St., 400294 Cluj-Napoca, Romania
- Centre for Systems Biology, Biodiversity and Bioresources, Babeș-Bolyai University, 5-7 Clinicilor St., 400006 Cluj-Napoca, Romania
| | - Dávid Vozik
- Research Institute on Bioengineering, Membrane Technology and Energetics, Faculty of Engineering, University of Veszprem, H-8200 Veszprém, Hungary; or or
| | - László Makrai
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, P.O. Box 22, H-1581 Budapest, Hungary;
- Correspondence: or (A.F.); (L.M.); Tel.: +36-(30)-490-9294 (A.F.); +36-(30)-271-2513 (L.M.)
| |
Collapse
|
47
|
Exposure of Mycobacterium abscessus to Environmental Stress and Clinically Used Antibiotics Reveals Common Proteome Response among Pathogenic Mycobacteria. Microorganisms 2020; 8:microorganisms8050698. [PMID: 32397563 PMCID: PMC7285101 DOI: 10.3390/microorganisms8050698] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/06/2020] [Accepted: 05/07/2020] [Indexed: 12/19/2022] Open
Abstract
Mycobacterium abscessus subsp. abscessus (MAB) is a clinically important nontuberculous mycobacterium (NTM) causing pulmonary infection in patients such as cystic fibrosis and bronchiectasis. MAB is naturally resistant to the majority of available antibiotics. In attempts to identify the fundamental response of MAB to aerobic, anaerobic, and biofilm conditions (as it is encountered in patients) and during exposure to antibiotics, we studied bacterial proteome using tandem mass tag mass spectrometry sequencing. Numerous de novo synthesized proteins belonging to diverse metabolic pathways were found in anaerobic and biofilm conditions, including glycolysis/gluconeogenesis, tricarboxylic acid (TCA) cycle, oxidative phosphorylation, nitrogen metabolism, and glyoxylate and dicarboxylate metabolism. Upon exposure to amikacin and linezolid under stress environments, MAB displayed metabolic enrichment for glycerophospholipid metabolism and oxidative phosphorylation. By comparing proteomes of two significant NTMs, MAB and M. avium subsp. hominissuis, we found highly synthesized shared enzymes of oxidative phosphorylation, TCA cycle, glycolysis/gluconeogenesis, glyoxylate/dicarboxylate, nitrogen metabolism, peptidoglycan biosynthesis, and glycerophospholipid/glycerolipid metabolism. The activation of peptidoglycan and fatty acid biosynthesis pathways indicates the attempt of bacteria to modify the cell wall, influencing the susceptibility to antibiotics. This study establishes global changes in the synthesis of enzymes promoting the metabolic shift and enhancing the pathogen resistance to antibiotics within different environments.
Collapse
|
48
|
|