1
|
Huang WC, Dwija IBNP, Hashimoto M, Wu JJ, Wang MC, Kao CY, Lin WH, Wang S, Teng CH. Peptidoglycan endopeptidase MepM of uropathogenic Escherichia coli contributes to competitive fitness during urinary tract infections. BMC Microbiol 2024; 24:190. [PMID: 38816687 PMCID: PMC11137974 DOI: 10.1186/s12866-024-03290-9] [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: 09/01/2023] [Accepted: 04/02/2024] [Indexed: 06/01/2024] Open
Abstract
BACKGROUND Urinary tract infections (UTIs) are common bacterial infections, primarily caused by uropathogenic Escherichia coli (UPEC), leading to significant health issues and economic burden. Although antibiotics have been effective in treating UPEC infections, the rise of antibiotic-resistant strains hinders their efficacy. Hence, identifying novel bacterial targets for new antimicrobial approaches is crucial. Bacterial factors required for maintaining the full virulence of UPEC are the potential target. MepM, an endopeptidase in E. coli, is involved in the biogenesis of peptidoglycan, a major structure of bacterial envelope. Given that the bacterial envelope confronts the hostile host environment during infections, MepM's function could be crucial for UPEC's virulence. This study aims to explore the role of MepM in UPEC pathogenesis. RESULTS MepM deficiency significantly impacted UPEC's survival in urine and within macrophages. Moreover, the deficiency hindered the bacillary-to-filamentous shape switch which is known for aiding UPEC in evading phagocytosis during infections. Additionally, UPEC motility was downregulated due to MepM deficiency. As a result, the mepM mutant displayed notably reduced fitness in causing UTIs in the mouse model compared to wild-type UPEC. CONCLUSIONS This study provides the first evidence of the vital role of peptidoglycan endopeptidase MepM in UPEC's full virulence for causing UTIs. MepM's contribution to UPEC pathogenesis may stem from its critical role in maintaining the ability to resist urine- and immune cell-mediated killing, facilitating the morphological switch, and sustaining motility. Thus, MepM is a promising candidate target for novel antimicrobial strategies.
Collapse
Affiliation(s)
- Wen-Chun Huang
- Institute of Molecular Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Ida Bagus Nyoman Putra Dwija
- Department of Clinical Microbiology, Faculty of Medicine, Udayana University, Denpasar, Bali, Indonesia
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Masayuki Hashimoto
- Institute of Molecular Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jiunn-Jong Wu
- Department of Medical Laboratory Science and Biotechnology, Asia University, Taichung, Taiwan
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
| | - Ming-Cheng Wang
- Division of Nephrology, Department of Internal Medicine, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung University, Tainan, Taiwan
| | - Cheng-Yen Kao
- Institute of Microbiology and Immunology, College of Life Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Wei-Hung Lin
- Department of Internal Medicine, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung University, Tainan, Taiwan
| | - Shuying Wang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
| | - Ching-Hao Teng
- Institute of Molecular Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
| |
Collapse
|
2
|
Liew KC, O’Keeffe J, Rajandas H, Lee YP, Harris O, Parimannan S, Croft L, Athan E. Insights into the Evolution of P. aeruginosa Antimicrobial Resistance in a Patient Undergoing Intensive Therapy. Antibiotics (Basel) 2023; 12:antibiotics12030483. [PMID: 36978350 PMCID: PMC10044667 DOI: 10.3390/antibiotics12030483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/21/2023] [Accepted: 02/25/2023] [Indexed: 03/03/2023] Open
Abstract
Whole genome sequencing (WGS) provides insights into the evolution of antimicrobial resistance, an urgent global health threat. Using WGS, we observe evolutionary adaptation of a Pseudomonas aeruginosa strain within an immunocompromised patient undergoing antibiotic therapy. Two blood isolates (EA-86 and EA-87) from the patient evolved separate adaptations for antibiotic resistance, while sharing common adaptive mutations for host immune evasion. In EA-86, a silencing mutation in the antibiotic efflux pump repressor, NfxB, increased antibiotic resistance, while in EA-87, a similar mutation was seen in the antibiotic efflux pump repressor mexR. The number of genomic variants between the two isolates give a divergence time estimate of the order of 1000 generations. This time is sufficient for a bacterial lineage to have evolved an SNP in every position in the genome and been fixed if advantageous. This demonstrates the evolutionary adaptive power accessible to bacteria and the timescale for a brute-force functional survey of the SNP fitness landscape.
Collapse
Affiliation(s)
- Kwee Chin Liew
- Australian Clinical Labs, Department of Microbiology, Geelong, VIC 3220, Australia
- Barwon Health, University Hospital Geelong, Geelong, VIC 3220, Australia
| | - Jessica O’Keeffe
- Barwon Health, University Hospital Geelong, Geelong, VIC 3220, Australia
| | - Heera Rajandas
- Centre of Excellence for Omics-Driven Computational Biodiscovery (COMBio), Faculty of Applied Sciences, AIMST University, Bedong 08100, Kedah, Malaysia
- Deakin Genomic Centre, Deakin University, Geelong, VIC 3216, Australia
| | - Yin Peng Lee
- Deakin Genomic Centre, Deakin University, Geelong, VIC 3216, Australia
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC 3216, Australia
| | - Owen Harris
- Australian Clinical Labs, Department of Microbiology, Geelong, VIC 3220, Australia
- Barwon Health, University Hospital Geelong, Geelong, VIC 3220, Australia
- School of Medicine, Deakin University, Geelong, VIC 3220, Australia
| | - Sivachandran Parimannan
- Centre of Excellence for Omics-Driven Computational Biodiscovery (COMBio), Faculty of Applied Sciences, AIMST University, Bedong 08100, Kedah, Malaysia
- Deakin Genomic Centre, Deakin University, Geelong, VIC 3216, Australia
- Correspondence: (S.P.); (L.C.)
| | - Larry Croft
- Deakin Genomic Centre, Deakin University, Geelong, VIC 3216, Australia
- School of Medicine, Deakin University, Geelong, VIC 3220, Australia
- Correspondence: (S.P.); (L.C.)
| | - Eugene Athan
- Barwon Health, University Hospital Geelong, Geelong, VIC 3220, Australia
- School of Medicine, Deakin University, Geelong, VIC 3220, Australia
- Geelong Centre for Emerging Infectious Diseases, Geelong, VIC 3220, Australia
| |
Collapse
|
3
|
Stærk K, Grønnemose RB, Palarasah Y, Lund L, Andersen TE. Intracellular uropathogenic Escherichia coli are undetectable in urinary bladders after oral mecillinam treatment: An experimental study in a pig model of cystitis. Microb Pathog 2022; 173:105817. [DOI: 10.1016/j.micpath.2022.105817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 09/26/2022] [Accepted: 10/04/2022] [Indexed: 11/05/2022]
|
4
|
Abell-King C, Costas A, Duggin IG, Söderström B. Bacterial filamentation during urinary tract infections. PLoS Pathog 2022; 18:e1010950. [PMID: 36454736 PMCID: PMC9714745 DOI: 10.1371/journal.ppat.1010950] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Affiliation(s)
- Charlotte Abell-King
- Australian Institute for Microbiology and Infection, University of Technology Sydney, ULTIMO, Australia
| | - Ariana Costas
- Australian Institute for Microbiology and Infection, University of Technology Sydney, ULTIMO, Australia
| | - Iain G. Duggin
- Australian Institute for Microbiology and Infection, University of Technology Sydney, ULTIMO, Australia
| | - Bill Söderström
- Australian Institute for Microbiology and Infection, University of Technology Sydney, ULTIMO, Australia
- * E-mail:
| |
Collapse
|
5
|
López‐Escarpa D, Castanheira S, García‐del Portillo F. OmpR and Prc contribute to switch the Salmonella morphogenetic program in response to phagosome cues. Mol Microbiol 2022; 118:477-493. [PMID: 36115022 PMCID: PMC9827838 DOI: 10.1111/mmi.14982] [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: 07/01/2022] [Revised: 09/08/2022] [Accepted: 09/13/2022] [Indexed: 01/12/2023]
Abstract
Salmonella enterica serovar Typhimurium infects eukaryotic cells residing within membrane-bound phagosomes. In this compartment, the pathogen replaces the morphogenetic penicillin-binding proteins 2 and 3 (PBP2/PBP3) with PBP2SAL /PBP3SAL , two proteins absent in Escherichia coli. The basis for this switch is unknown. Here, we show that PBP3 protein levels drop drastically when S. Typhimurium senses acidity, high osmolarity and nutrient scarcity, cues that activate virulence functions required for intra-phagosomal survival and proliferation. The protease Prc and the transcriptional regulator OmpR contribute to lower PBP3 levels whereas OmpR stimulates PBP2SAL /PBP3SAL production. Surprisingly, despite being essential for division in E. coli, PBP3 levels also drop in non-pathogenic and pathogenic E. coli exposed to phagosome cues. Such exposure alters E. coli morphology resulting in very long bent and twisted filaments indicative of failure in the cell division and elongation machineries. None of these aberrant shapes are detected in S. Typhimurium. Expression of PBP3SAL restores cell division in E. coli exposed to phagosome cues although the cells retain elongation defects in the longitudinal axis. By switching the morphogenetic program, OmpR and Prc allow S. Typhimurium to properly divide and elongate inside acidic phagosomes maintaining its cellular dimensions and the rod shape.
Collapse
Affiliation(s)
- David López‐Escarpa
- Laboratory of Intracellular Bacterial PathogensNational Centre for Biotechnology (CNB‐CSIC)MadridSpain
| | - Sónia Castanheira
- Laboratory of Intracellular Bacterial PathogensNational Centre for Biotechnology (CNB‐CSIC)MadridSpain
| | | |
Collapse
|
6
|
Metabolic and Morphotypic Trade-Offs within the Eco-Evolutionary Dynamics of Escherichia coli. Microbiol Spectr 2022; 10:e0067822. [PMID: 36169422 PMCID: PMC9602443 DOI: 10.1128/spectrum.00678-22] [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] [Indexed: 12/30/2022] Open
Abstract
Escherichia coli arbitrarily encompasses facultative anaerobic, rod-shaped bacteria with defined respiratory and fermentative types of metabolism. The species diversification has been further advanced by atypical strains whose features deviate from the essential species-specific morphological and metabolic cutoff. The morphological cutoff is exemplified by bacterial filamentation. E. coli filamentation has been studied from two different perspectives: the first considers filamentation as a result of adaptive strategies and response to stress, while the second is based on findings from the cell division of E. coli's conditional mutants. Another cutoff is represented by E. coli's inability to use citrate as a sole carbon and energy source. In this study, we compared two atypical E. coli strains that belong to the same neuroinvasive ecovar but exhibit either of the two phenotypes that deviate from the species' features. While E. coli RS218 exists in the form of filaments incapable of growth on citrate, strain IHE3034 is represented as normal-sized bacteria able to ferment citrate under oxic conditions in the presence of glucose; in this paper, we show that these two phenotypes result from a bona fide trade-off. With the help of comparative proteomics and metabolomics, we discovered the proteome required for the upkeep of these phenotypes. The metabolic profiles of both strains reveal that under aerobic conditions, RS218 undergoes oxidative metabolism, while IHE3034 undergoes anaerobic respiration. Finally, we show that the use of citrate and filament formation are both linked in a trade-off occurring via a c-di-GMP-dependent phase variation event. IMPORTANCE Aerobic use of citrate and filamentous growth are arbitrary cutoffs for the Escherichia coli species. The strains that exhibit them as stable phenotypes are called atypical. In this study, we compare two atypical neuroinvasive E. coli strains, which alternatively display either of these phenotypes. We present the proteome and metabolome required for the maintenance of filamentous growth and show that anaerobic nitrate respiration is the main requirement for the use of citrate. The fact that the two phenotypes are differentially expressed by each strain prompted us to check if they are part of a trade-off. Indeed, these atypical characters are reversible and result from a c-di-GMP phase variation event. Thus, we revealed hidden links between stable morphological and metabolic phenotypes and provided information about alternative evolutionary pathways for the survival of E. coli strains in various host niches.
Collapse
|
7
|
Khan F, Jeong GJ, Tabassum N, Mishra A, Kim YM. Filamentous morphology of bacterial pathogens: regulatory factors and control strategies. Appl Microbiol Biotechnol 2022; 106:5835-5862. [PMID: 35989330 DOI: 10.1007/s00253-022-12128-1] [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] [Received: 05/19/2022] [Revised: 08/03/2022] [Accepted: 08/06/2022] [Indexed: 11/24/2022]
Abstract
Several studies have demonstrated that when exposed to physical, chemical, and biological stresses in the environment, many bacteria (Gram-positive and Gram-negative) change their morphology from a normal cell to a filamentous shape. The formation of filamentous morphology is one of the survival strategies against environmental stress and protection against phagocytosis or protist predators. Numerous pathogenic bacteria have shown filamentous morphologies when examined in vivo or in vitro. During infection, certain pathogenic bacteria adopt a filamentous shape inside the cell to avoid phagocytosis by immune cells. Filamentous morphology has also been seen in biofilms formed on biotic or abiotic surfaces by certain bacteria. As a result, in addition to protecting against phagocytosis by immune cells or predators, the filamentous shape aids in biofilm adhesion or colonization to biotic or abiotic surfaces. Furthermore, these filamentous morphologies of bacterial pathogens lead to antimicrobial drug resistance. Clinically, filamentous morphology has become one of the most serious challenges in treating bacterial infection. The current review went into great detail about the various factors involved in the change of filamentous morphology and the underlying mechanisms. In addition, the review discussed a control strategy for suppressing filamentous morphology in order to combat bacterial infections. Understanding the mechanism underlying the filamentous morphology induced by various environmental conditions will aid in drug development and lessen the virulence of bacterial pathogens. KEY POINTS: • The bacterial filamentation morphology is one of the survival mechanisms against several environmental stress conditions and protection from phagocytosis by host cells and protist predators. • The filamentous morphologies in bacterial pathogens contribute to enhanced biofilm formation, which develops resistance properties against antimicrobial drugs. • Filamentous morphology has become one of the major hurdles in treating bacterial infection, hence controlling strategies employed for inhibiting the filamentation morphology from combating bacterial infections.
Collapse
Affiliation(s)
- Fazlurrahman Khan
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea. .,Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea.
| | - Geum-Jae Jeong
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Nazia Tabassum
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan, 48513, Republic of Korea
| | - Akanksha Mishra
- Department of Biotechnology, Division of Research and Development, Lovely Professional University, Phagwara, Punjab, 144001, India
| | - Young-Mog Kim
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea. .,Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea. .,Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea.
| |
Collapse
|
8
|
Söderström B, Pittorino MJ, Daley DO, Duggin IG. Assembly dynamics of FtsZ and DamX during infection-related filamentation and division in uropathogenic E. coli. Nat Commun 2022; 13:3648. [PMID: 35752634 PMCID: PMC9233674 DOI: 10.1038/s41467-022-31378-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 06/15/2022] [Indexed: 11/09/2022] Open
Abstract
During infection of bladder epithelial cells, uropathogenic Escherichia coli (UPEC) can stop dividing and grow into highly filamentous forms. Here, we find that some filaments of E. coli UTI89 released from infected cells grow very rapidly and by more than 100 μm before initiating division, whereas others do not survive, suggesting that infection-related filamentation (IRF) is a stress response that promotes bacterial dispersal. IRF is accompanied by unstable, dynamic repositioning of FtsZ division rings. In contrast, DamX, which is associated with normal cell division and is also essential for IRF, is distributed uniformly around the cell envelope during filamentation. When filaments initiate division to regenerate rod cells, DamX condenses into stable rings prior to division. The DamX rings maintain consistent thickness during constriction and remain at the septum until after membrane fusion. Deletion of damX affects vegetative cell division in UTI89 (but not in the model E. coli K-12), and, during infection, blocks filamentation and reduces bacterial cell integrity. IRF therefore involves DamX distribution throughout the membrane and prevention of FtsZ ring stabilization, leading to cell division arrest. DamX then reassembles into stable division rings for filament division, promoting dispersal and survival during infection.
Collapse
Affiliation(s)
- Bill Söderström
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Sydney, 2007, NSW, Australia.
| | - Matthew J Pittorino
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Sydney, 2007, NSW, Australia
| | - Daniel O Daley
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, 106 91, Sweden
| | - Iain G Duggin
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Sydney, 2007, NSW, Australia
| |
Collapse
|
9
|
Patatin-like phospholipase CapV in Escherichia coli - morphological and physiological effects of one amino acid substitution. NPJ Biofilms Microbiomes 2022; 8:39. [PMID: 35546554 PMCID: PMC9095652 DOI: 10.1038/s41522-022-00294-z] [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: 03/05/2021] [Accepted: 03/22/2022] [Indexed: 11/09/2022] Open
Abstract
In rod-shaped bacteria, morphological plasticity occurs in response to stress, which blocks cell division to promote filamentation. We demonstrate here that overexpression of the patatin-like phospholipase variant CapVQ329R, but not CapV, causes pronounced sulA-independent pyridoxine-inhibited cell filamentation in the Escherichia coli K-12-derivative MG1655 associated with restriction of flagella production and swimming motility. Conserved amino acids in canonical patatin-like phospholipase A motifs, but not the nucleophilic serine, are required to mediate CapVQ329R phenotypes. Furthermore, CapVQ329R production substantially alters the lipidome and colony morphotype including rdar biofilm formation with modulation of the production of the biofilm activator CsgD, and affects additional bacterial traits such as the efficiency of phage infection and antimicrobial susceptibility. Moreover, genetically diverse commensal and pathogenic E. coli strains and Salmonella typhimurium responded with cell filamentation and modulation in colony morphotype formation to CapVQ329R expression. In conclusion, this work identifies the CapV variant CapVQ329R as a pleiotropic regulator, emphasizes a scaffold function for patatin-like phospholipases, and highlights the impact of the substitution of a single conserved amino acid for protein functionality and alteration of host physiology.
Collapse
|
10
|
Transcriptional alterations in bladder epithelial cells in response to infection with different morphological states of uropathogenic Escherichia coli. Sci Rep 2022; 12:486. [PMID: 35017565 PMCID: PMC8752619 DOI: 10.1038/s41598-021-04396-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 12/16/2021] [Indexed: 12/22/2022] Open
Abstract
Uropathogenic Escherichia coli (UPEC) may undergo a cyclic cascade of morphological alterations that are believed to enhance the potential of UPEC to evade host responses and re-infect host cell. However, knowledge on the pathogenic potential and host activation properties of UPEC during the morphological switch is limited. Microarray analysis was performed on mRNA isolated from human bladder epithelial cells (HBEP) after exposure to three different morphological states of UPEC (normal coliform, filamentous form and reverted form). Cells stimulated with filamentous bacteria showed the lowest number of significant gene alterations, although the number of enriched gene ontology classes was high suggesting diverse effects on many different classes of host genes. The normal coliform was in general superior in stimulating transcriptional activity in HBEP cells compared to the filamentous and reverted form. Top-scored gene entities activated by all three morphological states included IL17C, TNFAIP6, TNF, IL20, CXCL2, CXCL3, IL6 and CXCL8. The number of significantly changed canonical pathways was lower in HBEP cells stimulated with the reverted form (32 pathways), than in cells stimulated with the coliform (83 pathways) or filamentous bacteria (138 pathways). A host cell invasion assay showed that filamentous bacteria were unable to invade bladder cells, and that the number of intracellular bacteria was markedly lower in cells infected with the reverted form compared to the coliform. In conclusion, the morphological state of UPEC has major impact on the host bladder response both when evaluating the number and the identity of altered host genes and pathways.
Collapse
|
11
|
García V, Grønnemose RB, Torres-Puig S, Kudirkiene E, Piantelli M, Ahmed S, Andersen TE, Møller-Jensen J, Olsen JE, Herrero-Fresno A. Genome-wide analysis of fitness-factors in uropathogenic Escherichia coli during growth in laboratory media and during urinary tract infections. Microb Genom 2021; 7. [PMID: 34928200 PMCID: PMC8767336 DOI: 10.1099/mgen.0.000719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Uropathogenic Escherichia coli (UPEC) UTI89 is a well-characterized strain, which has mainly been used to study UPEC virulence during urinary tract infection (UTI). However, little is known on UTI89 key fitness-factors during growth in lab media and during UTI. Here, we used a transposon-insertion-sequencing approach (TraDIS) to reveal the UTI89 essential-genes for in vitro growth and fitness-gene-sets for growth in Luria broth (LB) and EZ-MOPS medium without glucose, as well as for human bacteriuria and mouse cystitis. A total of 293 essential genes for growth were identified and the set of fitness-genes was shown to differ depending on the growth media. A modified, previously validated UTI murine model, with administration of glucose prior to infection was applied. Selected fitness-genes for growth in urine and mouse-bladder colonization were validated using deletion-mutants. Novel fitness-genes, such as tusA, corA and rfaG; involved in sulphur-acquisition, magnesium-uptake, and LPS-biosynthesis, were proved to be important during UTI. Moreover, rfaG was confirmed as relevant in both niches, and therefore it may represent a target for novel UTI-treatment/prevention strategies.
Collapse
Affiliation(s)
- Vanesa García
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.,Laboratorio de Referencia de Escherichia coli (LREC), Departamento de Microbioloxía e Parasitoloxía, Facultade de Veterinaria, Universidade de Santiago de Compostela (USC), Lugo, Spain
| | - Rasmus B Grønnemose
- Research Unit of Clinical Microbiology, University of Southern Denmark and Odense University Hospital, Odense, Denmark
| | - Sergi Torres-Puig
- Institute for Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Egle Kudirkiene
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Mateo Piantelli
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Shahana Ahmed
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.,Department of Developmental, Molecular & Chemical Biology, Tufts University School of Medicine, Boston, MA, USA
| | - Thomas E Andersen
- Research Unit of Clinical Microbiology, University of Southern Denmark and Odense University Hospital, Odense, Denmark
| | - Jakob Møller-Jensen
- Institute for Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - John E Olsen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Ana Herrero-Fresno
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| |
Collapse
|
12
|
Stærk K, Grønnemose RB, Nielsen TK, Petersen NA, Palarasah Y, Torres-Puig S, Møller-Jensen J, Kolmos HJ, Lund L, Andersen TE. Escherichia coli type-1 fimbriae are critical to overcome initial bottlenecks of infection upon low-dose inoculation in a porcine model of cystitis. MICROBIOLOGY-SGM 2021; 167. [PMID: 34623231 PMCID: PMC8698211 DOI: 10.1099/mic.0.001101] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Most uropathogenic Escherichia coli (UPEC) express type-1 fimbriae (T1F), a key virulence factor for urinary tract infection (UTI) in mice. Evidence that conclusively associates this pilus with uropathogenesis in humans has, however, been difficult to obtain. We used an experimental porcine model of cystitis to assess the role of T1F in larger mammals more closely related to humans. Thirty-one pigs were infected with UPEC strain UTI89 or its T1F deficient mutant, UTI89ΔfimH, at inoculum titres of 102 to 108 colony forming units per millilitre. Urine and blood samples were collected and analysed 7 and 14 days post-inoculation, and whole bladders were removed at day 14 and analysed for uroepithelium-associated UPEC. All animals were consistently infected and reached high urine titres independent of inoculum titre. UTI89ΔfimH successfully colonized the bladders of 1/6 pigs compared to 6/6 for the wild-type strain. Intracellular UPEC were detectable in low numbers in whole bladder explants. In conclusion, low doses of UPEC are able to establish robust infections in pigs, similar to what is presumed in humans. T1F are critical for UPEC to surpass initial bottlenecks during infection but may be dispensable once infection is established. While supporting the conclusions from mice studies regarding a general importance of T1F in successfully infecting the host, the porcine UTI models’ natural high, more human-like, susceptibility to infection, allowed us to demonstrate a pivotal role of T1F in initial establishment of infection upon a realistic low-inoculum introduction of UPEC in the bladder.
Collapse
Affiliation(s)
- Kristian Stærk
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Rasmus Birkholm Grønnemose
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Thomas Kastberg Nielsen
- Research Unit of Urology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Nicky Anúel Petersen
- Research Unit of Urology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Yaseelan Palarasah
- Department of Cancer and Inflammation Research, Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Sergi Torres-Puig
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Jakob Møller-Jensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Hans Jørn Kolmos
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Lars Lund
- Research Unit of Urology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Urology, Odense University Hospital, Odense, Denmark
| | - Thomas Emil Andersen
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Clinical Microbiology, Odense University Hospital, Odense, Denmark
| |
Collapse
|
13
|
Phan MD, Bottomley AL, Peters KM, Harry EJ, Schembri MA. Uncovering novel susceptibility targets to enhance the efficacy of third-generation cephalosporins against ESBL-producing uropathogenic Escherichia coli. J Antimicrob Chemother 2021; 75:1415-1423. [PMID: 32073605 DOI: 10.1093/jac/dkaa023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 12/17/2019] [Accepted: 01/13/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Uropathogenic Escherichia coli (UPEC) are a major cause of urinary tract infection (UTI), one of the most common infectious diseases in humans. UPEC are increasingly associated with resistance to multiple antibiotics. This includes resistance to third-generation cephalosporins, a common class of antibiotics frequently used to treat UTI. METHODS We employed a high-throughput genome-wide screen using saturated transposon mutagenesis and transposon directed insertion-site sequencing (TraDIS) together with phenotypic resistance assessment to identify key genes required for survival of the MDR UPEC ST131 strain EC958 in the presence of the third-generation cephalosporin cefotaxime. RESULTS We showed that blaCMY-23 is the major ESBL gene in EC958 responsible for mediating resistance to cefotaxime. Our screen also revealed that mutation of genes involved in cell division and the twin-arginine translocation pathway sensitized EC958 to cefotaxime. The role of these cell-division and protein-secretion genes in cefotaxime resistance was confirmed through the construction of mutants and phenotypic testing. Mutation of these genes also sensitized EC958 to other cephalosporins. CONCLUSIONS This work provides an exemplar for the application of TraDIS to define molecular mechanisms of resistance to antibiotics. The identification of mutants that sensitize UPEC to cefotaxime, despite the presence of a cephalosporinase, provides a framework for the development of new approaches to treat infections caused by MDR pathogens.
Collapse
Affiliation(s)
- Minh-Duy Phan
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Amy L Bottomley
- The ithree institute, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Kate M Peters
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Elizabeth J Harry
- The ithree institute, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Mark A Schembri
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| |
Collapse
|
14
|
Matinfar S, Ahmadi M, Sisakht AM, Sadeghi J, Javedansirat S. Phylogenetic and antibiotics resistance in extended-spectrum B-lactamase (ESBL) Uropathogenic Escherichia coli: An update review. GENE REPORTS 2021. [DOI: 10.1016/j.genrep.2021.101168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
15
|
Huang WC, Hashimoto M, Shih YL, Wu CC, Lee MF, Chen YL, Wu JJ, Wang MC, Lin WH, Hong MY, Teng CH. Peptidoglycan Endopeptidase Spr of Uropathogenic Escherichia coli Contributes to Kidney Infections and Competitive Fitness During Bladder Colonization. Front Microbiol 2021; 11:586214. [PMID: 33391204 PMCID: PMC7774453 DOI: 10.3389/fmicb.2020.586214] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 11/25/2020] [Indexed: 11/27/2022] Open
Abstract
Uropathogenic Escherichia coli (UPEC) is the most common pathogen of urinary tract infections (UTIs). Antibiotic therapy is the conventional measure to manage such infections. However, the rapid emergence of antibiotic resistance has reduced the efficacy of antibiotic treatment. Given that the bacterial factors required for the full virulence of the pathogens are potential therapeutic targets, identifying such factors may facilitate the development of novel therapeutic strategies against UPEC UTIs. The peptidoglycan (PG) endopeptidase Spr (also named MepS) is required for PG biogenesis in E. coli. In the present study, we found that Spr deficiency attenuated the ability of UPEC to infect kidneys and induced a fitness defect during bladder colonization in a mouse model of UTI. Based on the liquid chromatography (LC)/mass spectrometry (MS)/MS analysis of the bacterial envelope, spr deletion changed the levels of some envelope-associated proteins, suggesting that Spr deficiency interfere with the components of the bacterial structure. Among the proteins, FliC was significantly downregulated in the spr mutant, which is resulted in reduced motility. Lack of Spr might hinder the function of the flagellar transcriptional factor FlhDC to decrease FliC expression. The motility downregulation contributed to the reduced fitness in urinary tract colonization. Additionally, spr deletion compromised the ability of UPEC to evade complement-mediated attack and to resist intracellular killing of phagocytes, consequently decreasing UPEC bloodstream survival. Spr deficiency also interfered with the UPEC morphological switch from bacillary to filamentous shapes during UTI. It is known that bacterial filamentation protects UPEC from phagocytosis by phagocytes. In conclusion, Spr deficiency was shown to compromise multiple virulence properties of UPEC, leading to attenuation of the pathogen in urinary tract colonization and bloodstream survival. These findings indicate that Spr is a potential antimicrobial target for further studies attempting to develop novel strategies in managing UPEC UTIs.
Collapse
Affiliation(s)
- Wen-Chun Huang
- Institute of Molecular Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Masayuki Hashimoto
- Institute of Molecular Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Ling Shih
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Chia-Ching Wu
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Mei-Feng Lee
- Department of Biotechnology, National Kaohsiung Normal University, Kaohsiung, Taiwan
| | - Ya-Lei Chen
- Department of Biotechnology, National Kaohsiung Normal University, Kaohsiung, Taiwan
| | - Jiunn-Jong Wu
- Department of Biotechnology and Laboratory Science in Medicine, School of Biomedical Science and Engineering, National Yang Ming University, Taipei, Taiwan
| | - Ming-Cheng Wang
- Division of Nephrology, Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wei-Hung Lin
- Division of Nephrology, Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Ming-Yuan Hong
- Department of Emergency Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Ching-Hao Teng
- Institute of Molecular Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
| |
Collapse
|
16
|
Caccamo PD, Jacq M, VanNieuwenhze MS, Brun YV. A Division of Labor in the Recruitment and Topological Organization of a Bacterial Morphogenic Complex. Curr Biol 2020; 30:3908-3922.e4. [PMID: 32795444 DOI: 10.1016/j.cub.2020.07.063] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 05/22/2020] [Accepted: 07/20/2020] [Indexed: 12/31/2022]
Abstract
Bacteria come in an array of shapes and sizes, but the mechanisms underlying diverse morphologies are poorly understood. The peptidoglycan (PG) cell wall is the primary determinant of cell shape. At the molecular level, morphological variation often results from the regulation of enzymes involved in cell elongation and division. These enzymes are spatially controlled by cytoskeletal scaffolding proteins, which both recruit and organize the PG synthesis complex. How then do cells define alternative morphogenic processes that are distinct from cell elongation and division? To address this, we have turned to the specific morphotype of Alphaproteobacterial stalks. Stalk synthesis is a specialized form of zonal growth, which requires PG synthesis in a spatially constrained zone to extend a thin cylindrical projection of the cell envelope. The morphogen SpmX defines the site of stalk PG synthesis, but SpmX is a PG hydrolase. How then does a non-cytoskeletal protein, SpmX, define and constrain PG synthesis to form stalks? Here, we report that SpmX and the bactofilin BacA act in concert to regulate stalk synthesis in Asticcacaulis biprosthecum. We show that SpmX recruits BacA to the site of stalk synthesis. BacA then serves as a stalk-specific topological organizer for PG synthesis activity, including its recruiter SpmX, at the base of the stalk. In the absence of BacA, cells produce "pseudostalks" that are the result of unconstrained PG synthesis. Therefore, the protein responsible for recruitment of a morphogenic PG remodeling complex, SpmX, is distinct from the protein that topologically organizes the complex, BacA.
Collapse
Affiliation(s)
- Paul D Caccamo
- Department of Biology, Indiana University, 1001 E. 3rd Street, Bloomington, IN 47405, USA; School of Life Sciences, Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ, USA
| | - Maxime Jacq
- Department of Biology, Indiana University, 1001 E. 3rd Street, Bloomington, IN 47405, USA; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Pavillon Roger-Gaudry, C.P. 6128, Succursale Centreville, Montréal, Canada
| | - Michael S VanNieuwenhze
- Department of Molecular and Cellular Biochemistry, 212 S. Hawthorne Drive, Indiana University, Bloomington, IN 47405, USA; Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, IN 47405, USA
| | - Yves V Brun
- Department of Biology, Indiana University, 1001 E. 3rd Street, Bloomington, IN 47405, USA; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Pavillon Roger-Gaudry, C.P. 6128, Succursale Centreville, Montréal, Canada.
| |
Collapse
|
17
|
Escherichia coli CFT073 Fitness Factors during Urinary Tract Infection: Identification Using an Ordered Transposon Library. Appl Environ Microbiol 2020; 86:AEM.00691-20. [PMID: 32358013 DOI: 10.1128/aem.00691-20] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 04/24/2020] [Indexed: 12/15/2022] Open
Abstract
Urinary tract infections (UTI), the second most diagnosed infectious disease worldwide, are caused primarily by uropathogenic Escherichia coli (UPEC), placing a significant financial burden on the health care system. High-throughput transposon mutagenesis combined with genome-targeted sequencing is a powerful technique to interrogate genomes for fitness genes. Genome-wide analysis of E. coli requires random libraries of at least 50,000 mutants to achieve 99.99% saturation; however, the traditional murine model of ascending UTI does not permit testing of large mutant pools due to a bottleneck during infection. To address this, an E. coli CFT073 transposon mutant ordered library of 9,216 mutants was created and insertion sites were identified. A single transposon mutant was selected for each gene to assemble a condensed library consisting of 2,913 unique nonessential mutants. Using a modified UTI model in BALB/c mice, we identified 36 genes important for colonizing the bladder, including purB, yihE, and carB Screening of the condensed library in vitro identified yigP and ubiG to be essential for growth in human urine. Additionally, we developed a novel quantitative PCR (qPCR) technique to identify genes with fitness defects within defined subgroups of related genes (e.g., genes encoding fimbriae, toxins, etc.) following UTI. The number of mutants within these subgroups circumvents bottleneck restriction and facilitates validation of multiple mutants to generate individual competitive indices. Collectively, this study investigates the bottleneck effects during UTI, provides two techniques for evading those effects that can be applied to other disease models, and contributes a genetic tool in prototype strain CFT073 to the field.IMPORTANCE Uropathogenic Escherichia coli strains cause most uncomplicated urinary tract infections (UTI), one of the most common infectious diseases worldwide. Random transposon mutagenesis techniques have been utilized to identify essential bacterial genes during infection; however, this has been met with limitations when applied to the murine UTI model. Conventional high-throughput transposon mutagenesis screens are not feasible because of inoculum size restrictions due to a bottleneck during infection. Our study utilizes a condensed ordered transposon library, limiting the number of mutants while maintaining the largest possible genome coverage. Screening of this library in vivo, and in human urine in vitro, identified numerous candidate fitness factors. Additionally, we have developed a novel technique using qPCR to quantify bacterial outputs following infection with small subgroups of transposon mutants. Molecular approaches developed in this study will serve as useful tools to probe in vivo models that are restricted by anatomical, physiological, or genetic bottleneck limitations.
Collapse
|
18
|
Bottomley AL, Peterson E, Iosifidis G, Yong AMH, Hartley-Tassell LE, Ansari S, McKenzie C, Burke C, Duggin IG, Kline KA, Harry EJ. The novel E. coli cell division protein, YtfB, plays a role in eukaryotic cell adhesion. Sci Rep 2020; 10:6745. [PMID: 32317661 PMCID: PMC7174318 DOI: 10.1038/s41598-020-63729-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 04/01/2020] [Indexed: 01/10/2023] Open
Abstract
Characterisation of protein function based solely on homology searches may overlook functions under specific environmental conditions, or the possibility of a protein having multiple roles. In this study we investigated the role of YtfB, a protein originally identified in a genome-wide screen to cause inhibition of cell division, and has demonstrated to localise to the Escherichia coli division site with some degree of glycan specificity. Interestingly, YtfB also shows homology to the virulence factor OapA from Haemophilus influenzae, which is important for adherence to epithelial cells, indicating the potential of additional function(s) for YtfB. Here we show that E. coli YtfB binds to N’acetylglucosamine and mannobiose glycans with high affinity. The loss of ytfB results in a reduction in the ability of the uropathogenic E. coli strain UTI89 to adhere to human kidney cells, but not to bladder cells, suggesting a specific role in the initial adherence stage of ascending urinary tract infections. Taken together, our results suggest a role for YtfB in adhesion to specific eukaryotic cells, which may be additional, or complementary, to its role in cell division. This study highlights the importance of understanding the possible multiple functions of proteins based on homology, which may be specific to different environmental conditions.
Collapse
Affiliation(s)
- Amy L Bottomley
- ithree institute, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Sydney, Australia.
| | - Elizabeth Peterson
- ithree institute, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Sydney, Australia
| | - Gregory Iosifidis
- ithree institute, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Sydney, Australia
| | - Adeline Mei Hui Yong
- Singapore Centre for Environmental Life Sciences Engineering (SCELSE) and the School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
| | | | - Shirin Ansari
- ithree institute, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Sydney, Australia
| | - Chris McKenzie
- ithree institute, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Sydney, Australia
| | - Catherine Burke
- ithree institute, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Sydney, Australia.,School of Life Sciences, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Sydney, Australia
| | - Iain G Duggin
- ithree institute, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Sydney, Australia
| | - Kimberly A Kline
- Singapore Centre for Environmental Life Sciences Engineering (SCELSE) and the School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Singapore
| | - Elizabeth J Harry
- ithree institute, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Sydney, Australia
| |
Collapse
|
19
|
Regulation of filamentation by bacteria and its impact on the productivity of compounds in biotechnological processes. Appl Microbiol Biotechnol 2020; 104:4631-4642. [DOI: 10.1007/s00253-020-10590-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/18/2020] [Accepted: 03/25/2020] [Indexed: 12/29/2022]
|
20
|
Nielsen TK, Petersen NA, Stærk K, Grønnemose RB, Palarasah Y, Nielsen LF, Kolmos HJ, Andersen TE, Lund L. A Porcine Model for Urinary Tract Infection. Front Microbiol 2019; 10:2564. [PMID: 31824442 PMCID: PMC6882375 DOI: 10.3389/fmicb.2019.02564] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 10/23/2019] [Indexed: 12/23/2022] Open
Abstract
Urinary tract infection (UTI) is the most common bacterial infectious disease with a high frequency of recurrence and the leading cause of septicemia. In vivo experimentation has contributed significantly to the present-day knowledge on UTI pathogenesis. This research has traditionally been based on murine models of UTI. Occasional conflicting results between UTI in mice and humans and increasing skepticism toward small rodent models in general warrant the need of novel large-animal infection models that better resemble the anatomy and physiology of humans, and thus better mimic the course of infection in humans. Here, we report, to our knowledge, the first large-animal model of cystitis. The model is based on pigs, and the protocol supports the establishment of persistent, non-ascending infection in this animal and is established without invasive surgical procedures, pain, and discomfort for the animal. The course of infection is monitored by cystoscopy, microscopy of bladder biopsies, and biochemical analysis of urine and blood samples. At termination, harvested whole bladders from infected pigs are analyzed for microbiological colonization using microscopy, histology, and viable bacterial counts. The model is a useful tool in future studies of UTI pathogenesis and opens up novel possibilities to bridge the current knowledge obtained from small-animal UTI models to UTI pathogenesis in humans.
Collapse
Affiliation(s)
- Thomas Kastberg Nielsen
- Research Unit of Urology, Department of Clinical Research, Odense University Hospital, University of Southern Denmark, Odense, Denmark
| | - Nicky Anúel Petersen
- Research Unit of Urology, Department of Clinical Research, Odense University Hospital, University of Southern Denmark, Odense, Denmark
| | - Kristian Stærk
- Research Unit of Clinical Microbiology, Department of Clinical Research, Odense University Hospital, University of Southern Denmark, Odense, Denmark
| | - Rasmus Birkholm Grønnemose
- Research Unit of Clinical Microbiology, Department of Clinical Research, Odense University Hospital, University of Southern Denmark, Odense, Denmark
| | - Yaseelan Palarasah
- Department of Cancer and Inflammation, University of Southern Denmark, Odense, Denmark
| | | | - Hans Jørn Kolmos
- Research Unit of Clinical Microbiology, Department of Clinical Research, Odense University Hospital, University of Southern Denmark, Odense, Denmark
| | - Thomas Emil Andersen
- Research Unit of Clinical Microbiology, Department of Clinical Research, Odense University Hospital, University of Southern Denmark, Odense, Denmark
| | - Lars Lund
- Research Unit of Urology, Department of Clinical Research, Odense University Hospital, University of Southern Denmark, Odense, Denmark
| |
Collapse
|
21
|
Kusuma KD, Payne M, Ung AT, Bottomley AL, Harry EJ. FtsZ as an Antibacterial Target: Status and Guidelines for Progressing This Avenue. ACS Infect Dis 2019; 5:1279-1294. [PMID: 31268666 DOI: 10.1021/acsinfecdis.9b00055] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The disturbing increase in the number of bacterial pathogens that are resistant to multiple, or sometimes all, current antibiotics highlights the desperate need to pursue the discovery and development of novel classes of antibacterials. The wealth of knowledge available about the bacterial cell division machinery has aided target-driven approaches to identify new inhibitor compounds. The main division target being pursued is the highly conserved and essential protein FtsZ. Despite very active research on FtsZ inhibitors for several years, this protein is not yet targeted by any commercial antibiotic. Here, we discuss the suitability of FtsZ as an antibacterial target for drug development and review progress achieved in this area. We use hindsight to highlight the gaps that have slowed progress in FtsZ inhibitor development and to suggest guidelines for concluding that FtsZ is actually the target of these molecules, a key missing link in several studies. In moving forward, a multidisciplinary, communicative, and collaborative process, with sharing of research expertise, is critical if we are to succeed.
Collapse
|
22
|
Adaptive Responses of Shewanella decolorationis to Toxic Organic Extracellular Electron Acceptor Azo Dyes in Anaerobic Respiration. Appl Environ Microbiol 2019; 85:AEM.00550-19. [PMID: 31175185 DOI: 10.1128/aem.00550-19] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 05/29/2019] [Indexed: 12/18/2022] Open
Abstract
Bacterial anaerobic respiration using an extracellular electron acceptor plays a predominant role in global biogeochemical cycles. However, the mechanisms of bacterial adaptation to the toxic organic pollutant as the extracellular electron acceptor during anaerobic respiration are not clear, which limits our ability to optimize the strategies for the bioremediation of a contaminated environment. Here, we report the physiological characteristics and the global gene expression of an ecologically successful bacterium, Shewanella decolorationis S12, when using a typical toxic organic pollutant, amaranth, as the extracellular electron acceptor. Our results revealed that filamentous shift (the cells stretched to fiber-like shapes as long as 18 μm) occurred under amaranth stress. Persistent stress led to a higher filamentous cell rate and decolorization ability in subcultural cells compared to parental strains. In addition, the expression of genes involved in cell division, the chemotaxis system, energy conservation, damage repair, and material transport in filamentous cells was significantly stimulated. The detailed roles of some genes with significantly elevated expressions in filamentous cells, such as the outer membrane porin genes ompA and ompW, the cytochrome c genes arpC and arpD, the global regulatory factor gene rpoS, and the methyl-accepting chemotaxis proteins genes SHD_2793 and SHD_0015, were identified by site-directed mutagenesis. Finally, a conceptual model was proposed to help deepen our insights into both the bacterial survival strategy when toxic organics were present and the mechanisms by which these toxic organics were biodegraded as the extracellular electron acceptors.IMPORTANCE Keeping toxic organic pollutants (TOPs) in tolerable levels is a huge challenge for bacteria in extremely unfavorable environments since TOPs could serve as energy substitutes but also as survival stresses when they are beyond some thresholds. This study focused on the underlying adaptive mechanisms of ecologically successful bacterium Shewanella decolorationis S12 when exposed to amaranth, a typical toxic organic pollutant, as the extracellular electron acceptor. Our results suggest that filamentous shift is a flexible and valid way to solve the dilemma between the energy resource and toxic stress. Filamentous cells regulate gene expression to enhance their degradation and detoxification capabilities, resulting in a strong viability. These novel adaptive responses to TOPs are believed to be an evolutionary achievement to succeed in harsh habitats and thus have great potential to be applied to environment engineering or synthetic biology if we could picture every unknown node in this pathway.
Collapse
|
23
|
Goormaghtigh F, Van Melderen L. Single-cell imaging and characterization of Escherichia coli persister cells to ofloxacin in exponential cultures. SCIENCE ADVANCES 2019; 5:eaav9462. [PMID: 31223653 PMCID: PMC6584399 DOI: 10.1126/sciadv.aav9462] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 05/10/2019] [Indexed: 06/02/2023]
Abstract
Bacterial persistence refers to the capacity of small subpopulations within clonal populations to tolerate antibiotics. Persisters are thought to originate from dormant cells in which antibiotic targets are less active and cannot be corrupted. Here, we report that in exponentially growing cultures, ofloxacin persisters originate from metabolically active cells: These cells are dividing before the addition of ofloxacin and do endure DNA damages during the treatment, similar to their nonpersister siblings. We observed that growth rate, DNA content, and SOS induction vary among persisters, as in the bulk of the population and therefore do not constitute predictive markers for persistence. Persister cells typically form long polynucleoid filaments and reach maximum SOS induction after removal of ofloxacin. Eventually, cell division resumes, giving rise to a new population. Our findings highlight the heterogeneity of persister cells and therefore the need to analyze these low-frequency phenotypic variants on a case-by-case basis at the single-cell level.
Collapse
Affiliation(s)
- Frédéric Goormaghtigh
- Cellular and Molecular Microbiology (CM2), Faculté des Sciences, Université Libre de Bruxelles (ULB), Gosselies, Belgium
| | - Laurence Van Melderen
- Cellular and Molecular Microbiology (CM2), Faculté des Sciences, Université Libre de Bruxelles (ULB), Gosselies, Belgium
| |
Collapse
|
24
|
Brzozowski RS, Huber M, Burroughs AM, Graham G, Walker M, Alva SS, Aravind L, Eswara PJ. Deciphering the Role of a SLOG Superfamily Protein YpsA in Gram-Positive Bacteria. Front Microbiol 2019; 10:623. [PMID: 31024470 PMCID: PMC6459960 DOI: 10.3389/fmicb.2019.00623] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 03/12/2019] [Indexed: 12/27/2022] Open
Abstract
Bacteria adapt to different environments by regulating cell division and several conditions that modulate cell division have been documented. Understanding how bacteria transduce environmental signals to control cell division is critical in understanding the global network of cell division regulation. In this article we describe a role for Bacillus subtilis YpsA, an uncharacterized protein of the SLOG superfamily of nucleotide and ligand-binding proteins, in cell division. We observed that YpsA provides protection against oxidative stress as cells lacking ypsA show increased susceptibility to hydrogen peroxide treatment. We found that the increased expression of ypsA leads to filamentation and disruption of the assembly of FtsZ, the tubulin-like essential protein that marks the sites of cell division in B. subtilis. We also showed that YpsA-mediated filamentation is linked to the growth rate. Using site-directed mutagenesis, we targeted several conserved residues and generated YpsA variants that are no longer able to inhibit cell division. Finally, we show that the role of YpsA is possibly conserved in Firmicutes, as overproduction of YpsA in Staphylococcus aureus also impairs cell division.
Collapse
Affiliation(s)
- Robert S Brzozowski
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, United States
| | - Mirella Huber
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, United States
| | - A Maxwell Burroughs
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, United States
| | - Gianni Graham
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, United States
| | - Merryck Walker
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, United States
| | - Sameeksha S Alva
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, United States
| | - L Aravind
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, United States
| | - Prahathees J Eswara
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, United States
| |
Collapse
|
25
|
Roles of the DedD Protein in Escherichia coli Cell Constriction. J Bacteriol 2019; 201:JB.00698-18. [PMID: 30692172 DOI: 10.1128/jb.00698-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 01/20/2019] [Indexed: 02/04/2023] Open
Abstract
Two key tasks of the bacterial septal-ring (SR) machinery during cell constriction are the generation of an inward-growing annulus of septal peptidoglycan (sPG) and the concomitant splitting of its outer edge into two layers of polar PG that will be inherited by the two new cell ends. FtsN is an essential SR protein that helps trigger the active constriction phase in Escherichia coli by inducing a self-enhancing cycle of processes that includes both sPG synthesis and splitting and that we refer to as the sPG loop. DedD is an SR protein that resembles FtsN in several ways. Both are bitopic inner membrane proteins with small N-terminal cytoplasmic parts and larger periplasmic parts that terminate with a SPOR domain. Though absence of DedD normally causes a mild cell-chaining phenotype, the protein is essential for division and survival of cells with limited FtsN activity. Here, we find that a small N-terminal portion of DedD (NDedD; DedD1-54) is required and sufficient to suppress ΔdedD-associated division phenotypes, and we identify residues within its transmembrane domain that are particularly critical to DedD function. Further analyses indicate that DedD and FtsN act in parallel to promote sPG synthesis, possibly by engaging different parts of the FtsBLQ subcomplex to induce a conformation that permits and/or stimulates the activity of sPG synthase complexes composed of FtsW, FtsI (PBP3), and associated proteins. We propose that, like FtsN, DedD promotes cell fission by stimulating sPG synthesis, as well as by providing positive feedback to the sPG loop.IMPORTANCE Cell division (cytokinesis) is a fundamental biological process that is incompletely understood for any organism. Division of bacterial cells relies on a ring-like machinery called the septal ring or divisome that assembles along the circumference of the mother cell at the site where constriction eventually occurs. In the well-studied bacterium Escherichia coli, this machinery contains over 30 distinct proteins. We identify functionally important parts of one of these proteins, DedD, and present evidence supporting a role for DedD in helping to induce and/or sustain a self-enhancing cycle of processes that are executed by fellow septal-ring proteins and that drive the active constriction phase of the cell division cycle.
Collapse
|
26
|
Meštrović T, Wilson J, Ljubin-Sternak S, Sviben M, Bedenić B, Barać A, Neuberg M, Drenjančević D, Ribić R, Kozina G. A 'pathogenic needle' in a 'commensal haystack': Genetic virulence signatures of Corynebacterium glucuronolyticum that may drive its infectious propensity for the male urogenital system. Med Hypotheses 2019; 126:38-41. [PMID: 31010496 DOI: 10.1016/j.mehy.2019.03.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 03/09/2019] [Accepted: 03/21/2019] [Indexed: 11/24/2022]
Abstract
The predominance of the genus Corynebacterium in the healthy male urogenital system contributes to the resident microbiome of not only the distal urethra, but potentially the proximal urethra and urinary bladder as well. However, for certain species in this genus, pathogenic potential was described, and the salient representative is Corynebacterium glucuronolyticum (C. glucuronolyticum) implicated in cases of urethritis and prostatitis in men. Nonetheless, some still question whether C. glucuronolyticum can actually be considered pathogenic or rather just a commensal species fortuitously isolated in patients with urogenital symptoms and/or syndromes. Although pathogen/commensal dichotomy is not always clear-cut, we hypothesize that specific genetic markers may expose C. glucuronolyticum as a convincingly pathogenic Corynebacterium. More specifically, characteristic pathogenic gene constellation inherent to this species (most notably the presence of specific sortase/SpaA-type pili gene clusters, but also the augmentative role of type VII secretion system) may significantly facilitate host tissue adhesion, with subsequent suppression/evasion of the immune response and acquisition of vitally important nutrients. Consequently, these genetic markers differentiate C. glucuronolyticum from its commensal counterparts, and give this species a pathogenic facet, which can be even further influenced by the Allee effect. In this paper we also propose a specific methodological approach on how to analyze C. glucuronolyticum epithelial colonization capacity and explore inceptive host cell-pathogen interactions that manipulate host environment and immune responses. This entails moving from approaches based primarily on overall homology of primary sequences towards specific structure-function studies to precisely evaluate all stakeholders involved in pili assemblage, cell adhesion and the expression of other virulence traits. In the era of high precision medicine, the hypothesized roles of C. glucuronolyticum adhesion systems in both virulence and nutrient acquisition may also reveal promising targets for future drug developments.
Collapse
Affiliation(s)
- Tomislav Meštrović
- Clinical Microbiology and Parasitology Unit, Polyclinic "Dr. Zora Profozić", Zagreb, Croatia; University Centre Varaždin, University North, Varaždin, Croatia.
| | - Jonas Wilson
- Sint Maarten Medical Center, Cay Hill, Sint Maarten (Dutch Part)
| | - Sunčanica Ljubin-Sternak
- University of Zagreb School of Medicine, Zagreb, Croatia; Clinical Microbiology Department, Teaching Institute of Public Health "Dr Andrija Štampar", Zagreb, Croatia
| | - Mario Sviben
- University of Zagreb School of Medicine, Zagreb, Croatia; Microbiology Service, Croatian National Institute of Public Health, Zagreb, Croatia
| | - Branka Bedenić
- University of Zagreb School of Medicine, Zagreb, Croatia; Department of Clinical and Molecular Microbiology, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Aleksandra Barać
- Clinic for Infectious and Tropical Diseases, Clinical Centre of Serbia, Belgrade, Serbia; Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | | | - Domagoj Drenjančević
- Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; University Hospital Centre, Osijek, Croatia
| | - Rosana Ribić
- University Centre Varaždin, University North, Varaždin, Croatia
| | - Goran Kozina
- University Centre Varaždin, University North, Varaždin, Croatia
| |
Collapse
|
27
|
Mediati DG, Burke CM, Ansari S, Harry EJ, Duggin IG. High-throughput sequencing of sorted expression libraries reveals inhibitors of bacterial cell division. BMC Genomics 2018; 19:781. [PMID: 30373517 PMCID: PMC6206680 DOI: 10.1186/s12864-018-5187-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 10/19/2018] [Indexed: 11/24/2022] Open
Abstract
Background Bacterial filamentation occurs when rod-shaped bacteria grow without dividing. To identify genetically encoded inhibitors of division that promote filamentation, we used cell sorting flow cytometry to enrich filamentous clones from an inducible expression library, and then identified the cloned DNA with high-throughput DNA sequencing. We applied the method to an expression library made from fragmented genomic DNA of uropathogenic E. coli UTI89, which undergoes extensive reversible filamentation in urinary tract infections and might encode additional regulators of division. Results We identified 55 genomic regions that reproducibly caused filamentation when expressed from the plasmid vector, and then further localized the cause of filamentation in several of these to specific genes or sub-fragments. Many of the identified genomic fragments encode genes that are known to participate in cell division or its regulation, and others may play previously-unknown roles. Some of the prophage genes identified were previously implicated in cell division arrest. A number of the other fragments encoded potential short transcripts or peptides. Conclusions The results provided evidence of potential new links between cell division and distinct cellular processes including central carbon metabolism and gene regulation. Candidate regulators of the UTI-associated filamentation response or others were identified amongst the results. In addition, some genomic fragments that caused filamentation may not have evolved to control cell division, but may have applications as artificial inhibitors. Our approach offers the opportunity to carry out in depth surveys of diverse DNA libraries to identify new genes or sequences encoding the capacity to inhibit division and cause filamentation. Electronic supplementary material The online version of this article (10.1186/s12864-018-5187-7) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Daniel G Mediati
- The ithree institute, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Catherine M Burke
- The ithree institute, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Shirin Ansari
- The ithree institute, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Elizabeth J Harry
- The ithree institute, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Iain G Duggin
- The ithree institute, University of Technology Sydney, Ultimo, NSW, 2007, Australia.
| |
Collapse
|
28
|
Frey M, Bobbala S, Karabin N, Scott E. Influences of nanocarrier morphology on therapeutic immunomodulation. Nanomedicine (Lond) 2018; 13:1795-1811. [PMID: 30084296 DOI: 10.2217/nnm-2018-0052] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Nanomaterials provide numerous advantages for the administration of therapeutics, particularly as carriers of immunomodulatory agents targeting specific immune cell populations during immunotherapy. While the physicochemical characteristics of nanocarriers have long been linked to their therapeutic efficacy and applications, focus has primarily been placed on assessing influences of size and surface chemistry. In addition to these materials properties, the nanostructure morphology, in other words, shape and aspect ratio, has emerged as an equally important feature of nanocarriers that can dictate mechanisms of endocytosis, biodistribution and degree of cytotoxicity. In this review, we will highlight how the morphological features of nanostructures influence the immune responses elicited during therapeutic immunomodulation.
Collapse
Affiliation(s)
- Molly Frey
- Interdisciplinary Biological Sciences Program, Northwestern University, Evanston, IL 60208, USA
| | - Sharan Bobbala
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Nicholas Karabin
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Evan Scott
- Interdisciplinary Biological Sciences Program, Northwestern University, Evanston, IL 60208, USA.,Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA.,Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208, USA.,Simpson Querrey Institute, Northwestern University, Chicago, IL 60611, USA.,Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL 60611, USA
| |
Collapse
|
29
|
Jorgenson MA, Young KD. YtfB, an OapA Domain-Containing Protein, Is a New Cell Division Protein in Escherichia coli. J Bacteriol 2018; 200:e00046-18. [PMID: 29686141 PMCID: PMC5996693 DOI: 10.1128/jb.00046-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 04/18/2018] [Indexed: 12/15/2022] Open
Abstract
While screening the Pfam database for novel peptidoglycan (PG) binding modules, we identified the OapA domain, which is annotated as a LysM-like domain. LysM domains bind PG and mediate localization to the septal ring. In the Gram-negative bacterium Escherichia coli, an OapA domain is present in YtfB, an inner membrane protein of unknown function but whose overproduction causes cells to filament. Together, these observations suggested that YtfB directly affects cell division, most likely through its OapA domain. Here, we show that YtfB accumulates at the septal ring and that its action requires the division-initiating protein FtsZ and, to a lesser extent, ZipA, an early recruit to the septalsome. While the loss of YtfB had no discernible impact, a mutant lacking both YtfB and DedD (a known cell division protein) grew as filamentous cells. The YtfB OapA domain by itself also localized to sites of division, and this localization was enhanced by the presence of denuded PGs. Finally, the OapA domain bound PG, though binding did not depend on the formation of denuded glycans. Collectively, our findings demonstrate that YtfB is a cell division protein whose function is related to cell wall hydrolases.IMPORTANCE All living cells must divide in order to thrive. In bacteria, this involves the coordinated activities of a large number of proteins that work in concert to constrict the cell. Knowing which proteins contribute to this process and how they function is fundamental. Here, we identify a new member of the cell division apparatus in the Gram-negative bacterium Escherichia coli whose function is related to the generation of a transient cell wall structure. These findings deepen our understanding of bacterial cell division.
Collapse
Affiliation(s)
- Matthew A Jorgenson
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Kevin D Young
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| |
Collapse
|
30
|
Mendez J, Cascales D, Garcia-Torrico AI, Guijarro JA. Temperature-Dependent Gene Expression in Yersinia ruckeri: Tracking Specific Genes by Bioluminescence During in Vivo Colonization. Front Microbiol 2018; 9:1098. [PMID: 29887855 PMCID: PMC5981175 DOI: 10.3389/fmicb.2018.01098] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 05/08/2018] [Indexed: 11/26/2022] Open
Abstract
Yersinia ruckeri is a bacterium causing fish infection processes at temperatures below the optimum for growth. A derivative Tn5 transposon was used to construct a library of Y. ruckeri mutants with transcriptional fusions between the interrupted genes and the promoterless luxCDABE and lacZY operons. In vitro analysis of β-galactosidase activity allowed the identification of 168 clones having higher expression at 18°C than at 28°C. Among the interrupted genes a SAM-dependent methyltransferase, a diguanylated cyclase, three genes involved in legionaminic acid synthesis and three transcriptional regulators were defined. In order to determine, via bioluminescence emission, the in vivo expression of some of these genes, two of the selected mutants were studied. In one of them, the acrR gene coding a repressor involved in regulation of the AcrAB-TolC expulsion pump was interrupted. This mutant was found to be highly resistant to compounds such as chloramphenicol, tetracycline, and ciprofloxacin. Although acrR mutation was not related to virulence in Y. ruckeri, this mutant was useful to analyze acrR expression in fish tissues in vivo. The other gene studied was osmY which is activated under osmotic stress and is involved in virulence. In this case, complemented mutant was used for experiments with fish. In vivo analysis of bioluminescence emission by these two strains showed higher values for acrR in gut, liver and adipose tissue, whereas osmY showed higher luminescence in gut and, at the end of the infection process, in muscle tissue. Similar results were obtained in ex vivo assays using rainbow trout tissues. The results indicated that this kind of approach was useful for the identification of genes related to virulence in Y. ruckeri and also for the in vivo and in vitro studies of each of the selected genes.
Collapse
Affiliation(s)
- Jessica Mendez
- Área de Microbiología, Departamento de Biología Funcional, Facultad de Medicina, Instituto de Biotecnología de Asturias, Universidad de Oviedo, Oviedo, Spain
| | - Desirée Cascales
- Área de Microbiología, Departamento de Biología Funcional, Facultad de Medicina, Instituto de Biotecnología de Asturias, Universidad de Oviedo, Oviedo, Spain
| | - Ana I Garcia-Torrico
- Área de Microbiología, Departamento de Biología Funcional, Facultad de Medicina, Instituto de Biotecnología de Asturias, Universidad de Oviedo, Oviedo, Spain
| | - Jose A Guijarro
- Área de Microbiología, Departamento de Biología Funcional, Facultad de Medicina, Instituto de Biotecnología de Asturias, Universidad de Oviedo, Oviedo, Spain
| |
Collapse
|
31
|
Purification of Intracellular Bacterial Communities during Experimental Urinary Tract Infection Reveals an Abundant and Viable Bacterial Reservoir. Infect Immun 2018; 86:IAI.00740-17. [PMID: 29378794 DOI: 10.1128/iai.00740-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 01/22/2018] [Indexed: 12/17/2022] Open
Abstract
Urinary tract infections (UTIs) are a major infection of humans, particularly affecting women. Recurrent UTIs can cause significant discomfort and expose patients to high levels of antibiotic use, which in turn contributes to the development of higher antibiotic resistance rates. Most UTIs are caused by uropathogenic Escherichia coli, which is able to form intracellular collections (termed intracellular bacterial communities [IBCs]) within the epithelial cells lining the bladder lumen. IBCs are seen in both infected mice and humans and are a potential cause of recurrent UTI. Genetic and molecular studies of IBCs have been hampered both by the low number of bacteria in IBCs relative to the number extracellular bacteria and by population bottlenecks that occur during IBC formation. We now report the development of a simple and rapid technique for isolating pure IBCs from experimentally infected mice. We verified the specificity and purity of the isolated IBCs via microscopy, gene expression, and culture-based methods. Our results further demonstrated that our isolation technique practically enables specific molecular studies of IBCs. In the first such direct measurement, we determined that a single epithelial cell containing an early IBC typically contains 103 viable bacteria. Our isolation technique complements recent progress in low-input, single-cell genomics to enable future genomic studies of the formation of IBCs and their activation pathways during recurrent UTI, which may lead to novel strategies to eliminate them from the bladder.
Collapse
|
32
|
Pedersen RM, Grønnemose RB, Stærk K, Asferg CA, Andersen TB, Kolmos HJ, Møller-Jensen J, Andersen TE. A Method for Quantification of Epithelium Colonization Capacity by Pathogenic Bacteria. Front Cell Infect Microbiol 2018; 8:16. [PMID: 29450193 PMCID: PMC5799267 DOI: 10.3389/fcimb.2018.00016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 01/12/2018] [Indexed: 11/13/2022] Open
Abstract
Most bacterial infections initiate at the mucosal epithelium lining the gastrointestinal, respiratory, and urogenital tracts. At these sites, bacterial pathogens must adhere and increase in numbers to effectively breach the outer barrier and invade the host. If the bacterium succeeds in reaching the bloodstream, effective dissemination again requires that bacteria in the blood, reestablish contact to distant endothelium sites and form secondary site foci. The infectious potential of bacteria is therefore closely linked to their ability to adhere to, colonize, and invade epithelial and endothelial surfaces. Measurement of bacterial adhesion to epithelial cells is therefore standard procedure in studies of bacterial virulence. Traditionally, such measurements have been conducted with microtiter plate cell cultures to which bacteria are added, followed by washing procedures and final quantification of retained bacteria by agar plating. This approach is fast and straightforward, but yields only a rough estimate of the adhesive properties of the bacteria upon contact, and little information on the ability of the bacterium to colonize these surfaces under relevant physiological conditions. Here, we present a method in which epithelia/endothelia are simulated by flow chamber-grown human cell layers, and infection is induced by seeding of pathogenic bacteria on these surfaces under conditions that simulate the physiological microenvironment. Quantification of bacterial adhesion and colonization of the cell layers is then performed by in situ time-lapse fluorescence microscopy and automatic detection of bacterial surface coverage. The method is demonstrated in three different infection models, simulating Staphylococcus aureus endothelial infection and Escherichia coli intestinal- and uroepithelial infection. The approach yields valuable information on the fitness of the bacterium to successfully adhere to and colonize epithelial surfaces and can be used to evaluate the influence of specific virulence genes, growth conditions, and antimicrobial treatment on this process.
Collapse
Affiliation(s)
- Rune M Pedersen
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| | - Rasmus B Grønnemose
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| | - Kristian Stærk
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| | - Cecilie A Asferg
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| | - Thea B Andersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Hans J Kolmos
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| | - Jakob Møller-Jensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Thomas E Andersen
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| |
Collapse
|
33
|
Caccamo PD, Brun YV. The Molecular Basis of Noncanonical Bacterial Morphology. Trends Microbiol 2017; 26:191-208. [PMID: 29056293 DOI: 10.1016/j.tim.2017.09.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 09/08/2017] [Accepted: 09/28/2017] [Indexed: 01/04/2023]
Abstract
Bacteria come in a wide variety of shapes and sizes. The true picture of bacterial morphological diversity is likely skewed due to an experimental focus on pathogens and industrially relevant organisms. Indeed, most of the work elucidating the genes and molecular processes involved in maintaining bacterial morphology has been limited to rod- or coccal-shaped model systems. The mechanisms of shape evolution, the molecular processes underlying diverse shapes and growth modes, and how individual cells can dynamically modulate their shape are just beginning to be revealed. Here we discuss recent work aimed at advancing our knowledge of shape diversity and uncovering the molecular basis for shape generation in noncanonical and morphologically complex bacteria.
Collapse
Affiliation(s)
- Paul D Caccamo
- Department of Biology, Indiana University, 1001 E. 3rd St, Bloomington, IN 47405, USA
| | - Yves V Brun
- Department of Biology, Indiana University, 1001 E. 3rd St, Bloomington, IN 47405, USA.
| |
Collapse
|
34
|
Abstract
Within the mammalian urinary tract uropathogenic bacteria face many challenges, including the shearing flow of urine, numerous antibacterial molecules, the bactericidal effects of phagocytes, and a scarcity of nutrients. These problems may be circumvented in part by the ability of uropathogenic Escherichia coli and several other uropathogens to invade the epithelial cells that line the urinary tract. By entering host cells, uropathogens can gain access to additional nutrients and protection from both host defenses and antibiotic treatments. Translocation through host cells can facilitate bacterial dissemination within the urinary tract, while the establishment of stable intracellular bacterial populations may create reservoirs for relapsing and chronic urinary tract infections. Here we review the mechanisms and consequences of host cell invasion by uropathogenic bacteria, with consideration of the defenses that are brought to bear against facultative intracellular pathogens within the urinary tract. The relevance of host cell invasion to the pathogenesis of urinary tract infections in human patients is also assessed, along with some of the emerging treatment options that build upon our growing understanding of the infectious life cycle of uropathogenic E. coli and other uropathogens.
Collapse
|
35
|
van Teeseling MCF, de Pedro MA, Cava F. Determinants of Bacterial Morphology: From Fundamentals to Possibilities for Antimicrobial Targeting. Front Microbiol 2017; 8:1264. [PMID: 28740487 PMCID: PMC5502672 DOI: 10.3389/fmicb.2017.01264] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 06/23/2017] [Indexed: 12/11/2022] Open
Abstract
Bacterial morphology is extremely diverse. Specific shapes are the consequence of adaptive pressures optimizing bacterial fitness. Shape affects critical biological functions, including nutrient acquisition, motility, dispersion, stress resistance and interactions with other organisms. Although the characteristic shape of a bacterial species remains unchanged for vast numbers of generations, periodical variations occur throughout the cell (division) and life cycles, and these variations can be influenced by environmental conditions. Bacterial morphology is ultimately dictated by the net-like peptidoglycan (PG) sacculus. The species-specific shape of the PG sacculus at any time in the cell cycle is the product of multiple determinants. Some morphological determinants act as a cytoskeleton to guide biosynthetic complexes spatiotemporally, whereas others modify the PG sacculus after biosynthesis. Accumulating evidence supports critical roles of morphogenetic processes in bacteria-host interactions, including pathogenesis. Here, we review the molecular determinants underlying morphology, discuss the evidence linking bacterial morphology to niche adaptation and pathogenesis, and examine the potential of morphological determinants as antimicrobial targets.
Collapse
Affiliation(s)
- Muriel C F van Teeseling
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, Umeå UniversityUmeå, Sweden
| | - Miguel A de Pedro
- Centro de Biología Molecular "Severo Ochoa" - Consejo Superior de Investigaciones Científicas, Universidad Autónoma de MadridMadrid, Spain
| | - Felipe Cava
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, Umeå UniversityUmeå, Sweden
| |
Collapse
|
36
|
Demirel I, Rangel I, Petersson U, Persson K, Kruse R. Transcriptional Alterations of Virulence-Associated Genes in Extended Spectrum Beta-Lactamase (ESBL)-Producing Uropathogenic Escherichia coli during Morphologic Transitions Induced by Ineffective Antibiotics. Front Microbiol 2017; 8:1058. [PMID: 28659883 PMCID: PMC5468405 DOI: 10.3389/fmicb.2017.01058] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/26/2017] [Indexed: 12/26/2022] Open
Abstract
It is known that an ineffective antibiotic treatment can induce morphological shifts in uropathogenic Escherichia coli (UPEC) but the virulence properties during these shifts remain to be studied. The present study examines changes in global gene expression patterns and in virulence factor-associated genes in an extended spectrum beta-lactamase (ESBL)-producing UPEC (ESBL019) during the morphologic transitions induced by an ineffective antibiotic and in the presence of human primary bladder epithelial cells. Microarray results showed that the different morphological states of ESBL019 had significant transcriptional alterations of a large number of genes (Transition; 7%, Filamentation; 32%, and Reverted 19% of the entities on the array). All three morphological states of ESBL019 were associated with a decreased energy metabolism, altered iron acquisition systems and altered adhesion expression. In addition, genes associated with LPS synthesis and bacterial motility was also altered in all the morphological states. Furthermore, the transition state induced a significantly higher release of TNF-α from bladder epithelial cells compared to all other morphologies, while the reverted state was unable to induce TNF-α release. Our findings show that the morphological shifts induced by ineffective antibiotics are associated with significant transcriptional virulence alterations in ESBL-producing UPEC, which may affect survival and persistence in the urinary tract.
Collapse
Affiliation(s)
- Isak Demirel
- School of Medical Sciences, Örebro UniversityÖrebro, Sweden.,Faculty of Medicine and Health, Inflammatory Response and Infection Susceptibility Centre, Örebro UniversityÖrebro, Sweden
| | - Ignacio Rangel
- School of Medical Sciences, Örebro UniversityÖrebro, Sweden.,Faculty of Medicine and Health, Nutrition-Gut-Brain Interactions Research Centre, Örebro UniversityÖrebro, Sweden
| | | | - Katarina Persson
- School of Medical Sciences, Örebro UniversityÖrebro, Sweden.,Faculty of Medicine and Health, Inflammatory Response and Infection Susceptibility Centre, Örebro UniversityÖrebro, Sweden
| | - Robert Kruse
- Faculty of Medicine and Health, Inflammatory Response and Infection Susceptibility Centre, Örebro UniversityÖrebro, Sweden.,Department of Clinical Research Laboratory, Faculty of Medicine and Health, Örebro UniversityÖrebro, Sweden
| |
Collapse
|
37
|
The SPOR Domain, a Widely Conserved Peptidoglycan Binding Domain That Targets Proteins to the Site of Cell Division. J Bacteriol 2017; 199:JB.00118-17. [PMID: 28396350 DOI: 10.1128/jb.00118-17] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Sporulation-related repeat (SPOR) domains are small peptidoglycan (PG) binding domains found in thousands of bacterial proteins. The name "SPOR domain" stems from the fact that several early examples came from proteins involved in sporulation, but SPOR domain proteins are quite diverse and contribute to a variety of processes that involve remodeling of the PG sacculus, especially with respect to cell division. SPOR domains target proteins to the division site by binding to regions of PG devoid of stem peptides ("denuded" glycans), which in turn are enriched in septal PG by the intense, localized activity of cell wall amidases involved in daughter cell separation. This targeting mechanism sets SPOR domain proteins apart from most other septal ring proteins, which localize via protein-protein interactions. In addition to SPOR domains, bacteria contain several other PG-binding domains that can exploit features of the cell wall to target proteins to specific subcellular sites.
Collapse
|
38
|
Madelung M, Kronborg T, Doktor TK, Struve C, Krogfelt KA, Møller-Jensen J. DFI-seq identification of environment-specific gene expression in uropathogenic Escherichia coli. BMC Microbiol 2017; 17:99. [PMID: 28438119 PMCID: PMC5404293 DOI: 10.1186/s12866-017-1008-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 04/12/2017] [Indexed: 12/23/2022] Open
Abstract
Background During infection of the urinary tract, uropathogenic Escherichia coli (UPEC) are exposed to different environments, such as human urine and the intracellular environments of bladder epithelial cells. Each environment elicits a distinct bacterial environment-specific transcriptional response. We combined differential fluorescence induction (DFI) with next-generation sequencing, collectively termed DFI-seq, to identify differentially expressed genes in UPEC strain UTI89 during growth in human urine and bladder cells. Results DFI-seq eliminates the need for iterative cell sorting of the bacterial library and yields a genome-wide view of gene expression. By analysing the gene expression of UPEC in human urine we found that genes involved in amino acid biosynthesis were upregulated. Deletion mutants lacking genes involved in arginine biosynthesis were outcompeted by the wild type during growth in human urine and inhibited in their ability to invade or proliferate in the J82 bladder epithelial cell line. Furthermore, DFI-seq was used to identify genes involved in invasion of J82 bladder epithelial cells. 56 genes were identified to be differentially expressed of which almost 60% encoded hypothetical proteins. One such gene UTI89_C5139, displayed increased adhesion and invasion of J82 cells when deleted from UPEC strain UTI89. Conclusions We demonstrate the usefulness of DFI-seq for identification of genes required for optimal growth of UPEC in human urine, as well as potential virulence genes upregulated during infection of bladder cell culture. DFI-seq holds potential for the study of bacterial gene expression in live-animal infection systems. By linking fitness genes, such as those genes involved in amino acid biosynthesis, to virulence, this study contributes to our understanding of UPEC pathophysiology. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-1008-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Michelle Madelung
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Tina Kronborg
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Thomas Koed Doktor
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Carsten Struve
- Department of Microbiology and Infection Control, Statens Serum Institut, Artillerivej 5, 2300, Copenhagen S, Denmark
| | - Karen Angeliki Krogfelt
- Department of Microbiology and Infection Control, Statens Serum Institut, Artillerivej 5, 2300, Copenhagen S, Denmark
| | - Jakob Møller-Jensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark.
| |
Collapse
|