1
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Burke Ó, Zeden MS, O'Gara JP. The pathogenicity and virulence of the opportunistic pathogen Staphylococcus epidermidis. Virulence 2024; 15:2359483. [PMID: 38868991 DOI: 10.1080/21505594.2024.2359483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 05/19/2024] [Indexed: 06/14/2024] Open
Abstract
The pervasive presence of Staphylococcus epidermidis and other coagulase-negative staphylococci on the skin and mucous membranes has long underpinned a casual disregard for the infection risk that these organisms pose to vulnerable patients in healthcare settings. Prior to the recognition of biofilm as an important virulence determinant in S. epidermidis, isolation of this microorganism in diagnostic specimens was often overlooked as clinically insignificant with potential delays in diagnosis and onset of appropriate treatment, contributing to the establishment of chronic infection and increased morbidity or mortality. While impressive progress has been made in our understanding of biofilm mechanisms in this important opportunistic pathogen, research into other virulence determinants has lagged S. aureus. In this review, the broader virulence potential of S. epidermidis including biofilm, toxins, proteases, immune evasion strategies and antibiotic resistance mechanisms is surveyed, together with current and future approaches for improved therapeutic interventions.
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Affiliation(s)
- Órla Burke
- Microbiology, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
| | | | - James P O'Gara
- Microbiology, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
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2
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Peran JE, Salvador-Reyes LA. Modified oxylipins as inhibitors of biofilm formation in Staphylococcus epidermidis. Front Pharmacol 2024; 15:1379643. [PMID: 38846101 PMCID: PMC11153713 DOI: 10.3389/fphar.2024.1379643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 04/23/2024] [Indexed: 06/09/2024] Open
Abstract
New approaches to combating microbial drug resistance are being sought, with the discovery of biofilm inhibitors considered as alternative arsenal for treating infections. Natural products have been at the forefront of antimicrobial discovery and serve as inspiration for the design of new antibiotics. We probed the potency, selectivity, and mechanism of anti-biofilm activity of modified oxylipins inspired by the marine natural product turneroic acid. Structure-activity relationship (SAR) evaluation revealed the importance of the trans-epoxide moiety, regardless of the position, for inhibiting biofilm formation. trans-12,13-epoxyoctadecanoic acid (1) and trans-9,10 epoxyoctadecanoic acid (4) selectively target the early stage of biofilm formation, with no effect on planktonic cells. These compounds interrupt the formation of a protective polysaccharide barrier by significantly upregulating the ica operon's transcriptional repressor. This was corroborated by docking experiment with SarA and scanning electron micrographs showing reduced biofilm aggregates and the absence of thread-like structures of extrapolymeric substances. In silico evaluation revealed that 1 and 4 can interfere with the AgrA-mediated communication language in Staphylococci, typical to the diffusible signal factor (DSF) capacity of lipophilic chains.
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Affiliation(s)
| | - Lilibeth A. Salvador-Reyes
- Marine Science Institute, College of Science, University of the Philippines Diliman, Quezon City, Philippines
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3
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Liu P, Kang X, Chen X, Luo X, Li C, Wang G. Quercetin targets SarA of methicillin-resistant Staphylococcus aureus to mitigate biofilm formation. Microbiol Spectr 2024; 12:e0272223. [PMID: 38018987 PMCID: PMC10783115 DOI: 10.1128/spectrum.02722-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 10/16/2023] [Indexed: 11/30/2023] Open
Abstract
IMPORTANCE Anti-biofilm is an important strategy against Staphylococcus aureus chronic infection. SarA is a positive regulator of biofilm formation in S. aureus. In this study, we identified the SarA inhibitor quercetin using computer simulation screening. Previous studies have shown that quercetin inhibits biofilm; however, the underlying mechanism remains unknown. This study revealed the inhibitory effect of quercetin on the SarA protein. We also isolated the SarA protein and confirmed its interaction with quercetin in vitro. Besides, the inhibitory effect of quercetin on the transcription and translation levels of the SarA protein was also determined. The effects of quercetin on S. aureus biofilm inhibition and biofilm components were consistent with the changes in the transcription level of biofilm-related genes regulated by SarA. In summary, our study revealed the mechanism by which quercetin affects biofilm formation by inhibiting the transcriptional regulator SarA of S. aureus.
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Affiliation(s)
- Panpan Liu
- College of Animal Science and Technology, Ningxia University, Yinchuan, China
| | - Xinyun Kang
- College of Animal Science and Technology, Ningxia University, Yinchuan, China
| | - Xiaohui Chen
- College of Animal Science and Technology, Ningxia University, Yinchuan, China
| | - Xiaofeng Luo
- College of Animal Science and Technology, Ningxia University, Yinchuan, China
| | - Caixia Li
- College of Animal Science and Technology, Ningxia University, Yinchuan, China
| | - Guiqin Wang
- College of Animal Science and Technology, Ningxia University, Yinchuan, China
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4
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Peng Q, Tang X, Dong W, Zhi Z, Zhong T, Lin S, Ye J, Qian X, Chen F, Yuan W. Carvacrol inhibits bacterial polysaccharide intracellular adhesin synthesis and biofilm formation of mucoid Staphylococcus aureus: an in vitro and in vivo study. RSC Adv 2023; 13:28743-28752. [PMID: 37807974 PMCID: PMC10552078 DOI: 10.1039/d3ra02711b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 09/25/2023] [Indexed: 10/10/2023] Open
Abstract
Staphylococcus aureus (S. aureus) is one of the important human pathogens and causes both superficial and systemic infections. More importantly, the formation of S. aureus biofilms, a main cause of its pathogenicity and drug resistance, has been a critical challenge in clinical treatment. Carvacrol, a plant-based natural product, has gained great interest for therapeutic purposes due to its effective biological activity with low cytotoxicity. The present study aimed to investigate the effect of carvacrol on anti-biofilm activity. Growth curve analysis showed that applying a sub-inhibitory concentration of carvacrol (4 μg mL-1) was not lethal to S. aureus SYN; however, the inhibition rate of biofilm formation was as high as 63.6%, and the clearance rate of mature biofilms was as high as 30.7%. In addition, carvacrol effectively reduced the production of biofilm-associated extracellular polysaccharides and showed no effect on eDNA release. Furthermore, qPCR analysis revealed that carvacrol significantly down-regulated the expression of icaA, icaB, icaC, agrA, and sarA (P < 0.05). The in vivo efficacy of carvacrol against biofilm infection was further verified with a biological model of G. mellonella larvae. The results showed that carvacrol was non-toxic to the larvae and can effectively increase the survival rate of the larvae infected with S. aureus strain SYN.
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Affiliation(s)
- Qi Peng
- Guangzhou Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious Diseases, King Med School of Laboratory Medicine, Guangzhou Medical University Guangzhou 510180 PR China
| | - Xiaohua Tang
- Guangzhou Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious Diseases, King Med School of Laboratory Medicine, Guangzhou Medical University Guangzhou 510180 PR China
- Department of Clinical Laboratory, Third Affiliated Hospital of Guangzhou Medical University Guangzhou 510150 PR China
| | - Wanyang Dong
- Guangzhou Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious Diseases, King Med School of Laboratory Medicine, Guangzhou Medical University Guangzhou 510180 PR China
| | - Ziling Zhi
- Guangzhou Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious Diseases, King Med School of Laboratory Medicine, Guangzhou Medical University Guangzhou 510180 PR China
| | - Tian Zhong
- Guangzhou Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious Diseases, King Med School of Laboratory Medicine, Guangzhou Medical University Guangzhou 510180 PR China
| | - Shunan Lin
- Guangzhou Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious Diseases, King Med School of Laboratory Medicine, Guangzhou Medical University Guangzhou 510180 PR China
| | - Jingyi Ye
- Guangzhou Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious Diseases, King Med School of Laboratory Medicine, Guangzhou Medical University Guangzhou 510180 PR China
| | - Xiping Qian
- Guangzhou Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious Diseases, King Med School of Laboratory Medicine, Guangzhou Medical University Guangzhou 510180 PR China
| | - Fu Chen
- Panyu District Health Management Center Guangzhou 511450 PR China
| | - Wenchang Yuan
- Guangzhou Key Laboratory for Clinical Rapid Diagnosis and Early Warning of Infectious Diseases, King Med School of Laboratory Medicine, Guangzhou Medical University Guangzhou 510180 PR China
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5
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Fu T, Fan Z, Li Y, Li Z, Zhao H, Feng Y, Xue G, Cui J, Yan C, Gan L, Feng J, Yuan J, You F. Roles of the Crp/Fnr Family Regulator ArcR in the Hemolysis and Biofilm of Staphylococcus aureus. Microorganisms 2023; 11:1656. [PMID: 37512829 PMCID: PMC10384999 DOI: 10.3390/microorganisms11071656] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 06/20/2023] [Accepted: 06/22/2023] [Indexed: 07/30/2023] Open
Abstract
Staphylococcus aureus is an opportunistic human pathogen that is often involved in severe infections such as pneumonia and sepsis in which bacterial virulence factors play a key role. Infections caused by S. aureus are often difficult to eradicate, particularly when they are associated with biofilm. The physiological roles of the Crp/Fnr family regulator ArcR are elusive in S. aureus. In this study, it was found that the deletion of arcR increased the hemolytic ability and biofilm formation in S. aureus. Differential gene expression analysis by RNA-seq and real-time quantitative reverse transcription PCR showed that genes associated with hemolytic ability (hla and hlb) and biofilm formation (icaA, icaB, icaC and icaD) were significantly upregulated compared with those in the wild-type strain. The results revealed that ArcR regulated the expression of the hla and ica operon by binding to their promoter regions, respectively. This study provided new insights into the functional importance of ArcR in regulating the virulence and biofilm of S. aureus.
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Affiliation(s)
- Tongtong Fu
- School of Basic Medical Sciences, Peking University, Beijing 100020, China
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Zheng Fan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Yujie Li
- Department of Life Science and Medicine, University of Science and Technology of China, Hefei 230026, China
| | - Zhoufei Li
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Hanqing Zhao
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Yanling Feng
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Guanhua Xue
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Jinghua Cui
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Chao Yan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Lin Gan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Junxia Feng
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Jing Yuan
- Department of Bacteriology, Capital Institute of Pediatrics, Beijing 100020, China
| | - Fuping You
- School of Basic Medical Sciences, Peking University, Beijing 100020, China
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6
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Patel H, Rawat S. A genetic regulatory see-saw of biofilm and virulence in MRSA pathogenesis. Front Microbiol 2023; 14:1204428. [PMID: 37434702 PMCID: PMC10332168 DOI: 10.3389/fmicb.2023.1204428] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 05/30/2023] [Indexed: 07/13/2023] Open
Abstract
Staphylococcus aureus is one of the most common opportunistic human pathogens causing several infectious diseases. Ever since the emergence of the first methicillin-resistant Staphylococcus aureus (MRSA) strain decades back, the organism has been a major cause of hospital-acquired infections (HA-MRSA). The spread of this pathogen across the community led to the emergence of a more virulent subtype of the strain, i.e., Community acquired Methicillin resistant Staphylococcus aureus (CA-MRSA). Hence, WHO has declared Staphylococcus aureus as a high-priority pathogen. MRSA pathogenesis is remarkable because of the ability of this "superbug" to form robust biofilm both in vivo and in vitro by the formation of polysaccharide intercellular adhesin (PIA), extracellular DNA (eDNA), wall teichoic acids (WTAs), and capsule (CP), which are major components that impart stability to a biofilm. On the other hand, secretion of a diverse array of virulence factors such as hemolysins, leukotoxins, enterotoxins, and Protein A regulated by agr and sae two-component systems (TCS) aids in combating host immune response. The up- and downregulation of adhesion genes involved in biofilm formation and genes responsible for synthesizing virulence factors during different stages of infection act as a genetic regulatory see-saw in the pathogenesis of MRSA. This review provides insight into the evolution and pathogenesis of MRSA infections with a focus on genetic regulation of biofilm formation and virulence factors secretion.
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Affiliation(s)
| | - Seema Rawat
- Microbiology Laboratory, School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India
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7
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Shen L, Zhang J, Chen Y, Rao L, Wang X, Zhao H, Wang B, Xiao Y, Yu J, Xu Y, Shi J, Han W, Song Z, Yu F. Small-Molecule Compound CY-158-11 Inhibits Staphylococcus aureus Biofilm Formation. Microbiol Spectr 2023; 11:e0004523. [PMID: 37166296 PMCID: PMC10269684 DOI: 10.1128/spectrum.00045-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 04/19/2023] [Indexed: 05/12/2023] Open
Abstract
Staphylococcus aureus is an important human pathogen and brings about many community-acquired, hospital-acquired, and biofilm-associated infections worldwide. It tends to form biofilms, triggering the release of toxins and initiating resistance mechanisms. As a result of the development of S. aureus tolerance to antibiotics, there are few drugs can availably control biofilm-associated infections. In this study, we synthesized a novel small-molecule compound CY-158-11 (C22H14Cl2NO2Se2) and proved its inhibitory effect on the biofilm formation of S. aureus at a subinhibitory concentration (1/8 MIC). The subinhibitory concentration of CY-158-11 not only did not affect the growth of bacteria but also had no toxicity to A549 cells or G. mellonella. Total biofilm biomass was investigated by crystal violet staining, and the results were confirmed by SYTO 9 and PI staining through confocal laser scanning microscopy. Moreover, CY-158-11 effectively prevented initial attachment and repressed the production of PIA instead of autolysis. RT-qPCR analysis also exhibited significant suppression of the genes involved in biofilm formation. Taken together, CY-158-11 exerted its inhibitory effects against the biofilm formation in S. aureus by inhibiting cell adhesion and the expression of icaA related to PIA production. IMPORTANCE Most bacteria exist in the form of biofilms, often strongly adherent to various surfaces, causing bacterial resistance and chronic infections. In general, antibacterial drugs are not effective against biofilms. The small-molecule compound CY-158-11 inhibited the biofilm formation of S. aureus at a subinhibitory concentration. By hindering adhesion and PIA-mediated biofilm formation, CY-158-11 exhibits antibiofilm activity toward S. aureus. These findings point to a novel therapeutic agent for combating intractable S. aureus-biofilm-related infections.
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Affiliation(s)
- Li Shen
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Jiao Zhang
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yao Chen
- School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Lulin Rao
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Xinyi Wang
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Huilin Zhao
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Bingjie Wang
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yanghua Xiao
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Jingyi Yu
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yanlei Xu
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Junhong Shi
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Weihua Han
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Zengqiang Song
- School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Fangyou Yu
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
- Department of Laboratory Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
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8
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Cho JS, Yang D, Prabowo CPS, Ghiffary MR, Han T, Choi KR, Moon CW, Zhou H, Ryu JY, Kim HU, Lee SY. Targeted and high-throughput gene knockdown in diverse bacteria using synthetic sRNAs. Nat Commun 2023; 14:2359. [PMID: 37095132 PMCID: PMC10126203 DOI: 10.1038/s41467-023-38119-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Accepted: 04/17/2023] [Indexed: 04/26/2023] Open
Abstract
Synthetic sRNAs allow knockdown of target genes at translational level, but have been restricted to a limited number of bacteria. Here, we report the development of a broad-host-range synthetic sRNA (BHR-sRNA) platform employing the RoxS scaffold and the Hfq chaperone from Bacillus subtilis. BHR-sRNA is tested in 16 bacterial species including commensal, probiotic, pathogenic, and industrial bacteria, with >50% of target gene knockdown achieved in 12 bacterial species. For medical applications, virulence factors in Staphylococcus epidermidis and Klebsiella pneumoniae are knocked down to mitigate their virulence-associated phenotypes. For metabolic engineering applications, high performance Corynebacterium glutamicum strains capable of producing valerolactam (bulk chemical) and methyl anthranilate (fine chemical) are developed by combinatorial knockdown of target genes. A genome-scale sRNA library covering 2959 C. glutamicum genes is constructed for high-throughput colorimetric screening of indigoidine (natural colorant) overproducers. The BHR-sRNA platform will expedite engineering of diverse bacteria of both industrial and medical interest.
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Affiliation(s)
- Jae Sung Cho
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Dongsoo Yang
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02481, Republic of Korea
| | - Cindy Pricilia Surya Prabowo
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
| | - Mohammad Rifqi Ghiffary
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
- Systems Biology and Medicine Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), KAIST, Daejeon, 34141, Republic of Korea
| | - Taehee Han
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
| | - Kyeong Rok Choi
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
| | - Cheon Woo Moon
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
| | - Hengrui Zhou
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
| | - Jae Yong Ryu
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
- Department of Biotechnology, College of Science and Technology, Duksung Women's University, Seoul, Republic of Korea
| | - Hyun Uk Kim
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
- Systems Biology and Medicine Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), KAIST, Daejeon, 34141, Republic of Korea
- KAIST Institute for Artificial Intelligence, BioProcess Engineering Research Center and BioInformatics Research Center, KAIST, Daejeon, 34141, Republic of Korea
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea.
- KAIST Institute for Artificial Intelligence, BioProcess Engineering Research Center and BioInformatics Research Center, KAIST, Daejeon, 34141, Republic of Korea.
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9
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Gonçalves ASC, Leitão MM, Simões M, Borges A. The action of phytochemicals in biofilm control. Nat Prod Rep 2023; 40:595-627. [PMID: 36537821 DOI: 10.1039/d2np00053a] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Covering: 2009 to 2021Antimicrobial resistance is now rising to dangerously high levels in all parts of the world, threatening the treatment of an ever-increasing range of infectious diseases. This has becoming a serious public health problem, especially due to the emergence of multidrug-resistance among clinically important bacterial species and their ability to form biofilms. In addition, current anti-infective therapies have low efficacy in the treatment of biofilm-related infections, leading to recurrence, chronicity, and increased morbidity and mortality. Therefore, it is necessary to search for innovative strategies/antibacterial agents capable of overcoming the limitations of conventional antibiotics. Natural compounds, in particular those obtained from plants, have been exhibiting promising properties in this field. Plant secondary metabolites (phytochemicals) can act as antibiofilm agents through different mechanisms of action from the available antibiotics (inhibition of quorum-sensing, motility, adhesion, and reactive oxygen species production, among others). The combination of different phytochemicals and antibiotics have revealed synergistic or additive effects in biofilm control. This review aims to bring together the most relevant reports on the antibiofilm properties of phytochemicals, as well as insights into their structure and mechanistic action against bacterial pathogens, spanning December 2008 to December 2021.
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Affiliation(s)
- Ariana S C Gonçalves
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal.
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal
| | - Miguel M Leitão
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal.
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal
| | - Manuel Simões
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal.
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal
| | - Anabela Borges
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal.
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal
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10
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Li H, Song X, Liu W, Zhang Y, Guan H, Wu J, Yu S, Xue W. Revealing the antibacterial power of hydrogen-releasing PdH nanohydride against drug resistant Staphylococcus aureus: an in-depth mechanism study. J Mater Chem B 2023; 11:1495-1505. [PMID: 36655922 DOI: 10.1039/d2tb02068h] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Currently, multidrug resistant (MDR) bacterial infections are a great threat to public health, and the development of novel strategies for high efficiency combatting of MDR bacteria is in urgent demand. Hydrogen (H2) is a small gas with a high reducing ability, and plenty of recent studies have demonstrated its therapeutic effect on many diseases. However, the antibacterial effectiveness and mechanism of H2 against MDR bacteria are still unknown. In the present work, using PdH nanohydride with a temperature responsive H2-releasing property as the H2 source, we demonstrated that H2 was not only able to inhibit the growth of normal Staphylococcus aureus (S. aureus), but could also effectively eliminate single drug resistant S. aureus (CRSA) and multidrug resistant S. aureus (MRSA), as well as the biofilms formed by those bacteria. Moreover, an in-depth mechanism regarding the anti-antibiotic-resistance activity of H2 was elucidated by us, in which H2 exerted its antibacterial effect by firstly causing severe membrane damage, followed by boosting generation of intracellular ROS, which subsequently triggered DNA damage and finally led to bacterial death. The proposed mechanism was further verified by genomic analysis, where a cluster of genes related to bacterial membrane integrity, biofilm formation, metabolism and DNA functions was significantly perturbed by the released H2. In particular, H2 boosted intracellular ROS generation by destroying the redox homeostasis of bacterial metabolism. More importantly, we revealed that H2 was able to alleviate the antibiotic resistance of CRSA and MRSA by significantly down-regulating the expression of many drug-resistant genes, e.g. the norG gene of CRSA, and fmtA, gpsB, sarA and marR genes of MRSA, as well as reducing the minimal inhibitory concentration (MIC) of ciprofloxacin/ampicillin against CRSA/MRSA. The findings in our work suggested that H2 therapy is a promising tool for combating antibiotic-resistant bacteria.
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Affiliation(s)
- Hui Li
- Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Guangdong Provincial Engineering and Technological Research Center for Drug Carrier Development, Department of Biomedical Engineering, Jinan University, Guangzhou 510632, China.
| | - Xiling Song
- Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Guangdong Provincial Engineering and Technological Research Center for Drug Carrier Development, Department of Biomedical Engineering, Jinan University, Guangzhou 510632, China.
| | - Wenkang Liu
- Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Guangdong Provincial Engineering and Technological Research Center for Drug Carrier Development, Department of Biomedical Engineering, Jinan University, Guangzhou 510632, China.
| | - Yu Zhang
- Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Guangdong Provincial Engineering and Technological Research Center for Drug Carrier Development, Department of Biomedical Engineering, Jinan University, Guangzhou 510632, China.
| | - Heyuan Guan
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Department of Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
| | - Junlin Wu
- Institute of microbiology, Guangdong Academy of sciences, Guangzhou 510632, China.
| | - Siming Yu
- Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Guangdong Provincial Engineering and Technological Research Center for Drug Carrier Development, Department of Biomedical Engineering, Jinan University, Guangzhou 510632, China.
| | - Wei Xue
- Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Guangdong Provincial Engineering and Technological Research Center for Drug Carrier Development, Department of Biomedical Engineering, Jinan University, Guangzhou 510632, China.
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11
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Liu P, Zhao Z, Tang J, Wang A, Zhao D, Yang Y. Early Antimicrobial Evaluation of Nanostructured Surfaces Based on Bacterial Biological Properties. ACS Biomater Sci Eng 2022; 8:4976-4986. [PMID: 36223479 DOI: 10.1021/acsbiomaterials.2c00559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nanostructured physical antibacterial surfaces are of great interest due to the increasing antibiotic resistance. In this work, the titania nanotube (TNT) array, a potential physical antibacterial surface, was used for antimicrobial evaluation. The early antibacterial properties of TNTs were assessed based on three growth phases of Staphylococcus aureus (S. aureus), and the physical factors influencing the antibacterial properties were comprehensively discussed. The results show apparent early antibacterial effects of TNTs, including the anti-initial attachment during the lag phase, the inhibition of proliferation and bactericidal effect during the logarithmic phase, and the inhibition of biofilm formation during the stationary phase. These antimicrobial effects are closely related to the combined influence of various physical properties of TNTs, such as diameter, hydrophilicity, roughness, and charge. The present work suggests that the evaluation of the early antimicrobial behavior of biomaterials should pay more attention on the biological characteristics of bacteria.
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Affiliation(s)
- Pingting Liu
- Hunan Key Laboratory of Oral Health Research & Xiangya Stomatological Hospital & Xiangya School of Stomatology, Central South University, Changsha, Hunan 410008, China.,College of Biology, Hunan University, Changsha, Hunan 410082, China
| | - Zhili Zhao
- Department of Oral and Maxillofacial Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410010, China
| | - Jincheng Tang
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Anqi Wang
- College of Biology, Hunan University, Changsha, Hunan 410082, China
| | - Dapeng Zhao
- College of Biology, Hunan University, Changsha, Hunan 410082, China
| | - Yan Yang
- Hunan Key Laboratory of Oral Health Research & Xiangya Stomatological Hospital & Xiangya School of Stomatology, Central South University, Changsha, Hunan 410008, China
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12
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Manna AC, Leo S, Girel S, González-Ruiz V, Rudaz S, Francois P, Cheung AL. Teg58, a small regulatory RNA, is involved in regulating arginine biosynthesis and biofilm formation in Staphylococcus aureus. Sci Rep 2022; 12:14963. [PMID: 36056144 PMCID: PMC9440087 DOI: 10.1038/s41598-022-18815-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 08/19/2022] [Indexed: 12/02/2022] Open
Abstract
Staphylococcus aureus adapts to different environments by sensing and responding to diverse environmental cues. The responses are coordinately regulated by regulatory proteins, and small regulatory RNAs at the transcriptional and translational levels. Here, we characterized teg58, a SarA repressed sRNA, using ChIP-Seq and RNA-Seq analysis of a sarA mutant. Phenotypic and genetic analyses indicated that inactivation of teg58 led to reduced biofilm formation in a process that is independent of SarA, agr, PIA, and PSMs. RNA-Seq analysis of teg58 mutant revealed up-regulation of arginine biosynthesis genes (i.e., argGH) as well as the ability of the mutant to grow in a chemical defined medium (CDM) lacking L-arginine. Exogenous L-arginine or endogenous induction of argGH led to decreased biofilm formation in parental strains. Further analysis in vitro and in vivo demonstrated that the specific interaction between teg58 and the argGH occurred at the post-transcriptional level to repress arginine synthesis. Biochemical and genetic analyses of various arginine catabolic pathway genes demonstrated that the catabolic pathway did not play a significant role in reduced biofilm formation in the teg58 mutant. Overall, results suggest that teg58 is a regulatory sRNA that plays an important role in modulating arginine biosynthesis and biofilm formation in S. aureus.
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Affiliation(s)
- Adhar C Manna
- Department of Microbiology & Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA.
| | - Stefano Leo
- Genomic Research Laboratory, Service of Infectious Diseases, Geneva University Hospitals and University Medical Center, Rue Michel-Servet 1, 1211, Geneva 4, Switzerland
| | - Sergey Girel
- Institute of Pharmaceutical Sciences of Western Switzerland (ISPSO), School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland
- University Medical Center, Rue Michel-Servet 1, 1211, Geneva 4, Switzerland
| | - Víctor González-Ruiz
- Institute of Pharmaceutical Sciences of Western Switzerland (ISPSO), School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland
- University Medical Center, Rue Michel-Servet 1, 1211, Geneva 4, Switzerland
| | - Serge Rudaz
- Institute of Pharmaceutical Sciences of Western Switzerland (ISPSO), School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland
- University Medical Center, Rue Michel-Servet 1, 1211, Geneva 4, Switzerland
| | - Patrice Francois
- Genomic Research Laboratory, Service of Infectious Diseases, Geneva University Hospitals and University Medical Center, Rue Michel-Servet 1, 1211, Geneva 4, Switzerland
| | - Ambrose L Cheung
- Department of Microbiology & Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, 03755, USA
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13
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Cai Z, Mo Z, Zheng S, Lan S, Xie S, Lu J, Tang C, Shen Z. Flavaspidic acid BB combined with mupirocin improves its anti-bacterial and anti-biofilm activities against Staphylococcus epidermidis. BMC Microbiol 2022; 22:179. [PMID: 35840879 PMCID: PMC9284735 DOI: 10.1186/s12866-022-02578-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 06/06/2022] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND The increase in drug-resistant opportunistic pathogenic bacteria, especially of antibiotic-resistant Staphylococcus epidermidis (S. epidermidis), has led to difficulties in the treatment of skin and soft tissue infections (SSTI). The major reason for bacterial resistance is the formation of bacterial biofilm. Here, we report a promising combination therapy of flavaspidic acid BB (BB) and mupirocin, which can effectively eradicate the biofilm of S. epidermidis and eliminate its drug resistance. RESULT The susceptibility test showed that the combination of BB and mupirocin has good antibacterial and antibiofilm activities, and the fractional inhibitory concentration index (FICI) of BB combined with mupirocin was 0.51 ± 0.00 ~ 0.75 ± 0.05, showing synergistic effect. Moreover, the time-kill curve assay results indicated that the combination of drugs can effectively inhibit the planktonic S. epidermidis. After drugs treatment, the drug-combination showed significantly inhibitory effects on the metabolic activity and total biomass in each stage of biofilm formation. The synergistic effect is likely related to the adhesion between bacteria, which is confirmed by field emission scanning electron microscope. And the expression level of aap, sarA and agrA genes were detected by real-time quantitative PCR (qRT-PCR). CONCLUSION Our study provides the experimental data for the use of BB for the clinical treatment of skin infections and further demonstrate the potential of BB as a novel biofilm inhibitor.
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Affiliation(s)
- Zhiling Cai
- School of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Zitong Mo
- School of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Shiqian Zheng
- School of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Shihua Lan
- School of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Shengjun Xie
- School of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Jinghui Lu
- The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou, China
| | - Chunping Tang
- School of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, China
| | - Zhibin Shen
- School of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, China.
- Guangdong Provincial Engineering Center of Topical Precise Drug Delivery System, Guangdong Pharmaceutical University, Guangzhou, China.
- Guangdong Cosmetics Engineering &Technology Research Center, Guangdong Pharmaceutical University, Guangzhou, China.
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14
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Luzala MM, Muanga CK, Kyana J, Safari JB, Zola EN, Mbusa GV, Nuapia YB, Liesse JMI, Nkanga CI, Krause RWM, Balčiūnaitienė A, Memvanga PB. A Critical Review of the Antimicrobial and Antibiofilm Activities of Green-Synthesized Plant-Based Metallic Nanoparticles. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:1841. [PMID: 35683697 PMCID: PMC9182092 DOI: 10.3390/nano12111841] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 04/03/2022] [Accepted: 04/05/2022] [Indexed: 02/01/2023]
Abstract
Metallic nanoparticles (MNPs) produced by green synthesis using plant extracts have attracted huge interest in the scientific community due to their excellent antibacterial, antifungal and antibiofilm activities. To evaluate these pharmacological properties, several methods or protocols have been successfully developed and implemented. Although these protocols were mostly inspired by the guidelines from national and international regulatory bodies, they suffer from a glaring absence of standardization of the experimental conditions. This situation leads to a lack of reproducibility and comparability of data from different study settings. To minimize these problems, guidelines for the antimicrobial and antibiofilm evaluation of MNPs should be developed by specialists in the field. Being aware of the immensity of the workload and the efforts required to achieve this, we set out to undertake a meticulous literature review of different experimental protocols and laboratory conditions used for the antimicrobial and antibiofilm evaluation of MNPs that could be used as a basis for future guidelines. This review also brings together all the discrepancies resulting from the different experimental designs and emphasizes their impact on the biological activities as well as their interpretation. Finally, the paper proposes a general overview that requires extensive experimental investigations to set the stage for the future development of effective antimicrobial MNPs using green synthesis.
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Affiliation(s)
- Miryam M. Luzala
- Laboratory of Pharmaceutics and Phytopharmaceutical Drug Development, Faculty of Pharmaceutical Sciences, University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo; (M.M.L.); (C.K.M.); (E.N.Z.); (C.I.N.)
| | - Claude K. Muanga
- Laboratory of Pharmaceutics and Phytopharmaceutical Drug Development, Faculty of Pharmaceutical Sciences, University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo; (M.M.L.); (C.K.M.); (E.N.Z.); (C.I.N.)
| | - Joseph Kyana
- Department of Pharmacy, Faculty of Medecine and Pharmacy, University of Kisangani, Kisangani XI B.P. 2012, Democratic Republic of the Congo;
| | - Justin B. Safari
- Department of Pharmacy, Faculty of Pharmaceutical Sciences and Public Health, Official University of Bukavu, Bukavu B.P. 570, Democratic Republic of the Congo;
- Department of Chemistry, Faculty of Science, Rhodes University, P.O. Box 94, Makhana 6140, South Africa
| | - Eunice N. Zola
- Laboratory of Pharmaceutics and Phytopharmaceutical Drug Development, Faculty of Pharmaceutical Sciences, University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo; (M.M.L.); (C.K.M.); (E.N.Z.); (C.I.N.)
| | - Grégoire V. Mbusa
- Centre Universitaire de Référence de Surveillance de la Résistance aux Antimicrobiens (CURS-RAM), Faculty of Pharmaceutical Sciences, University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo; (G.V.M.); (J.-M.I.L.)
- Laboratory of Experimental and Pharmaceutical Microbiology, Faculty of Pharmaceutical Sciences, University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo
| | - Yannick B. Nuapia
- Laboratory of Toxicology, Faculty of Pharmaceutical Sciences, University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo;
| | - Jean-Marie I. Liesse
- Centre Universitaire de Référence de Surveillance de la Résistance aux Antimicrobiens (CURS-RAM), Faculty of Pharmaceutical Sciences, University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo; (G.V.M.); (J.-M.I.L.)
- Laboratory of Experimental and Pharmaceutical Microbiology, Faculty of Pharmaceutical Sciences, University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo
| | - Christian I. Nkanga
- Laboratory of Pharmaceutics and Phytopharmaceutical Drug Development, Faculty of Pharmaceutical Sciences, University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo; (M.M.L.); (C.K.M.); (E.N.Z.); (C.I.N.)
| | - Rui W. M. Krause
- Department of Chemistry, Faculty of Science, Rhodes University, P.O. Box 94, Makhana 6140, South Africa
- Center for Chemico- and Bio-Medicinal Research (CCBR), Faculty of Science, Rhodes University, P.O. Box 94, Makhana 6140, South Africa
| | - Aistė Balčiūnaitienė
- Lithuanian Research Centre for Agriculture and Forestry, Institute of Horticulture, 54333 Babtai, Lithuania;
| | - Patrick B. Memvanga
- Laboratory of Pharmaceutics and Phytopharmaceutical Drug Development, Faculty of Pharmaceutical Sciences, University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo; (M.M.L.); (C.K.M.); (E.N.Z.); (C.I.N.)
- Department of Pharmacy, Faculty of Medecine and Pharmacy, University of Kisangani, Kisangani XI B.P. 2012, Democratic Republic of the Congo;
- Department of Pharmacy, Faculty of Pharmaceutical Sciences and Public Health, Official University of Bukavu, Bukavu B.P. 570, Democratic Republic of the Congo;
- Centre de Recherche et d’Innovation Technologique en Environnement et en Sciences de la Santé (CRITESS), University of Kinshasa, Kinshasa XI B.P. 212, Democratic Republic of the Congo
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15
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Colonization and Infection of Indwelling Medical Devices by Staphylococcus aureus with an Emphasis on Orthopedic Implants. Int J Mol Sci 2022; 23:ijms23115958. [PMID: 35682632 PMCID: PMC9180976 DOI: 10.3390/ijms23115958] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 02/08/2023] Open
Abstract
The use of indwelling medical devices has constantly increased in recent years and has revolutionized the quality of life of patients affected by different diseases. However, despite the improvement of hygiene conditions in hospitals, implant-associated infections remain a common and serious complication in prosthetic surgery, mainly in the orthopedic field, where infection often leads to implant failure. Staphylococcus aureus is the most common cause of biomaterial-centered infection. Upon binding to the medical devices, these bacteria proliferate and develop dense communities encased in a protective matrix called biofilm. Biofilm formation has been proposed as occurring in several stages-(1) attachment; (2) proliferation; (3) dispersal-and involves a variety of host and staphylococcal proteinaceous and non-proteinaceous factors. Moreover, biofilm formation is strictly regulated by several control systems. Biofilms enable staphylococci to avoid antimicrobial activity and host immune response and are a source of persistent bacteremia as well as of localized tissue destruction. While considerable information is available on staphylococcal biofilm formation on medical implants and important results have been achieved on the treatment of biofilms, preclinical and clinical applications need to be further investigated. Thus, the purpose of this review is to gather current studies about the mechanism of infection of indwelling medical devices by S. aureus with a special focus on the biochemical factors involved in biofilm formation and regulation. We also provide a summary of the current therapeutic strategies to combat biomaterial-associated infections and highlight the need to further explore biofilm physiology and conduct research for innovative anti-biofilm approaches.
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16
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Teichmann P, Both A, Wolz C, Hornef MW, Rohde H, Yazdi AS, Burian M. The Staphylococcus epidermidis Transcriptional Profile During Carriage. Front Microbiol 2022; 13:896311. [PMID: 35558117 PMCID: PMC9087046 DOI: 10.3389/fmicb.2022.896311] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 04/08/2022] [Indexed: 11/29/2022] Open
Abstract
The virulence factors of the opportunistic human pathogen Staphylococcus epidermidis have been a main subject of research. In contrast, limited information is available on the mechanisms that allow the bacterium to accommodate to the conditions during carriage, a prerequisite for pathogenicity. Here, we tested the hypothesis that the adaptation of S. epidermidis at different anatomical sites is reflected by differential gene regulation. We used qPCR to profile S. epidermidis gene expression in vivo in nose and skin swabs of 11 healthy individuals. Despite some heterogeneity between individuals, significant site-specific differences were detected. For example, expression of the S. epidermidis regulator sarA was found similarly in the nose and on the skin of all individuals. Also, genes encoding colonization and immune evasion factors (sdrG, capC, and dltA), as well as the sphingomyelinase encoding gene sph, were expressed at both anatomical sites. In contrast, expression of the global regulator agr was almost inactive in the nose but readily present on the skin. A similar site-specific expression profile was also identified for the putative chitinase-encoding SE0760. In contrast, expression of the autolysine-encoding gene sceD and the wall teichoic acid (WTA) biosynthesis gene tagB were more pronounced in the nose as compared to the skin. In summary, our analysis identifies site-specific gene expression patterns of S. epidermidis during colonization. In addition, the observed expression signature was significantly different from growth in vitro. Interestingly, the strong transcription of sphingomyelinase together with the low expression of genes encoding the tricarboxylic acid cycle (TCA) suggests very good nutrient supply in both anatomical niches, even on the skin where one might have suspected a rather lower nutrient supply compared to the nose.
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Affiliation(s)
- Pascâl Teichmann
- Department of Dermatology and Allergology, RWTH University Hospital Aachen, Aachen, Germany
| | - Anna Both
- Institute of Medical Microbiology, Virology and Hygiene, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Christiane Wolz
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tuebingen, Tuebingen, Germany
| | - Mathias W Hornef
- Institute of Medical Microbiology, RWTH University Hospital Aachen, Aachen, Germany
| | - Holger Rohde
- Institute of Medical Microbiology, Virology and Hygiene, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Amir S Yazdi
- Department of Dermatology and Allergology, RWTH University Hospital Aachen, Aachen, Germany
| | - Marc Burian
- Department of Dermatology and Allergology, RWTH University Hospital Aachen, Aachen, Germany
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17
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The Transcription Factor SpoVG Is of Major Importance for Biofilm Formation of Staphylococcus epidermidis under In Vitro Conditions, but Dispensable for In Vivo Biofilm Formation. Int J Mol Sci 2022; 23:ijms23063255. [PMID: 35328675 PMCID: PMC8949118 DOI: 10.3390/ijms23063255] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/14/2022] [Accepted: 03/16/2022] [Indexed: 12/13/2022] Open
Abstract
Staphylococcus epidermidis is a common cause of device related infections on which pathogens form biofilms (i.e., multilayered cell populations embedded in an extracellular matrix). Here, we report that the transcription factor SpoVG is essential for the capacity of S. epidermidis to form such biofilms on artificial surfaces under in vitro conditions. Inactivation of spoVG in the polysaccharide intercellular adhesin (PIA) producing S. epidermidis strain 1457 yielded a mutant that, unlike its parental strain, failed to produce a clear biofilm in a microtiter plate-based static biofilm assay. A decreased biofilm formation capacity was also observed when 1457 ΔspoVG cells were co-cultured with polyurethane-based peripheral venous catheter fragments under dynamic conditions, while the cis-complemented 1457 ΔspoVG::spoVG derivative formed biofilms comparable to the levels seen with the wild-type. Transcriptional studies demonstrated that the deletion of spoVG significantly altered the expression of the intercellular adhesion (ica) locus by upregulating the transcription of the ica operon repressor icaR and down-regulating the transcription of icaADBC. Electrophoretic mobility shift assays (EMSA) revealed an interaction between SpoVG and the icaA-icaR intergenic region, suggesting SpoVG to promote biofilm formation of S. epidermidis by modulating ica expression. However, when mice were challenged with the 1457 ΔspoVG mutant in a foreign body infection model, only marginal differences in biomasses produced on the infected catheter fragments between the mutant and the parental strain were observed. These findings suggest that SpoVG is critical for the PIA-dependent biofilm formation of S. epidermis under in vitro conditions, but is largely dispensable for biofilm formation of this skin commensal under in vivo conditions.
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18
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Wu S, Zhang J, Peng Q, Liu Y, Lei L, Zhang H. The Role of Staphylococcus aureus YycFG in Gene Regulation, Biofilm Organization and Drug Resistance. Antibiotics (Basel) 2021; 10:antibiotics10121555. [PMID: 34943766 PMCID: PMC8698359 DOI: 10.3390/antibiotics10121555] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/09/2021] [Accepted: 12/16/2021] [Indexed: 02/05/2023] Open
Abstract
Antibiotic resistance is a serious global health concern that may have significant social and financial consequences. Methicillin-resistant Staphylococcus aureus (MRSA) infection is responsible for substantial morbidity and leads to the death of 21.8% of infected patients annually. A lack of novel antibiotics has prompted the exploration of therapies targeting bacterial virulence mechanisms. The two-component signal transduction system (TCS) enables microbial cells to regulate gene expression and the subsequent metabolic processes that occur due to environmental changes. The YycFG TCS in S. aureus is essential for bacterial viability, the regulation of cell membrane metabolism, cell wall synthesis and biofilm formation. However, the role of YycFG-associated biofilm organization in S. aureus antimicrobial drug resistance and gene regulation has not been discussed in detail. We reviewed the main molecules involved in YycFG-associated cell wall biosynthesis, biofilm development and polysaccharide intercellular adhesin (PIA) accumulation. Two YycFG-associated regulatory mechanisms, accessory gene regulator (agr) and staphylococcal accessory regulator (SarA), were also discussed. We highlighted the importance of biofilm formation in the development of antimicrobial drug resistance in S. aureus infections. Data revealed that inhibition of the YycFG pathway reduced PIA production, biofilm formation and bacterial pathogenicity, which provides a potential target for the management of MRSA-induced infections.
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Affiliation(s)
- Shizhou Wu
- Department of Orthopedics, West China Hospital, Sichuan University, Chengdu 610041, China; (S.W.); (J.Z.); (Q.P.)
| | - Junqi Zhang
- Department of Orthopedics, West China Hospital, Sichuan University, Chengdu 610041, China; (S.W.); (J.Z.); (Q.P.)
| | - Qi Peng
- Department of Orthopedics, West China Hospital, Sichuan University, Chengdu 610041, China; (S.W.); (J.Z.); (Q.P.)
| | - Yunjie Liu
- West China School of Public Health, Sichuan University, Chengdu 610041, China;
| | - Lei Lei
- West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
- Correspondence: (L.L.); (H.Z.)
| | - Hui Zhang
- Department of Orthopedics, West China Hospital, Sichuan University, Chengdu 610041, China; (S.W.); (J.Z.); (Q.P.)
- Correspondence: (L.L.); (H.Z.)
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19
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Phuengmaung P, Panpetch W, Singkham-In U, Chatsuwan T, Chirathaworn C, Leelahavanichkul A. Presence of Candida tropicalis on Staphylococcus epidermidis Biofilms Facilitated Biofilm Production and Candida Dissemination: An Impact of Fungi on Bacterial Biofilms. Front Cell Infect Microbiol 2021; 11:763239. [PMID: 34746032 PMCID: PMC8569676 DOI: 10.3389/fcimb.2021.763239] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 10/04/2021] [Indexed: 12/28/2022] Open
Abstract
While Staphylococcus epidermidis (SE) is a common cause of infections in implanted prostheses and other indwelling devices, partly due to the biofilm formation, Candida tropicalis (CT) is an emerging Candida spp. with a potent biofilm-producing property. Due to the possible coexistence between SE and CT infection in the same patient, characteristics of the polymicrobial biofilms from both organisms might be different from those of the biofilms of each organism. Then, the exploration on biofilms, from SE with or without CT, and an evaluation on l-cysteine (an antibiofilm against both bacteria and fungi) were performed. As such, Candida incubation in preformed SE biofilms (SE > CT) produced higher biofilms than the single- (SE or CT) or mixed-organism (SE + CT) biofilms as determined by crystal violet staining and fluorescent confocal images with z-stack thickness analysis. In parallel, SE > CT biofilms demonstrated higher expression of icaB and icaC than other groups at 20 and 24 h of incubation, suggesting an enhanced matrix polymerization and transportation, respectively. Although organism burdens (culture method) from single-microbial biofilms (SE or CT) were higher than multi-organism biofilms (SE + CT and SE > CT), macrophage cytokine responses (TNF-α and IL-6) against SE > CT biofilms were higher than those in other groups in parallel to the profound biofilms in SE > CT. Additionally, sepsis severity in mice with subcutaneously implanted SE > CT catheters was more severe than in other groups as indicated by mortality rate, fungemia, serum cytokines (TNF-α and IL-6), and kidney and liver injury. Although CT grows upon preformed SE-biofilm production, the biofilm structures interfered during CT morphogenesis leading to the frailty of biofilm structure and resulting in the prominent candidemia. However, l-cysteine incubation together with the organisms in catheters reduced biofilms, microbial burdens, macrophage responses, and sepsis severity. In conclusion, SE > CT biofilms prominently induced biofilm matrix, fungemia, macrophage responses, and sepsis severity, whereas the microbial burdens were lower than in the single-organism biofilms. All biofilms were attenuated by l-cysteine.
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Affiliation(s)
- Pornpimol Phuengmaung
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Wimonrat Panpetch
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Uthaibhorn Singkham-In
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Tanittha Chatsuwan
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.,Antimicrobial Resistance and Stewardship Research Unit, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Chintana Chirathaworn
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Asada Leelahavanichkul
- Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.,Translational Research in Inflammation and Immunology Research Unit (TRIRU), Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
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20
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Wu S, Liu Y, Lei L, Zhang H. Antisense yycG modulates the susceptibility of Staphylococcus aureus to hydrogen peroxide via the sarA. BMC Microbiol 2021; 21:160. [PMID: 34053439 PMCID: PMC8165985 DOI: 10.1186/s12866-021-02218-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 05/05/2021] [Indexed: 02/08/2023] Open
Abstract
Background The infectious pathogen Staphylococcus aureus (S. aureus) is primarily associated with osteomyelitis. Hydrogen peroxide drainage is an effective antimicrobial treatment that has been adopted to combat S. aureus infections. Previous investigations have indicated that the antisense RNA (asRNA) strategy negatively modulates S. aureus YycFG TCS, and it significantly disrupts biofilm formation. However, the effects of the antisense yycG RNA (ASyycG) strategy on the susceptibility of biofilm-producing S. aureus to hydrogen peroxide and the mechanisms underlying this effect have not been elucidated to date. Results Overexpression of ASyycG inhibited the transcription of biofilm formation-related genes, including sarA and icaA. Additionally, the CFU counts and the live bacterial ratios of ASyycG biofilm-producing S. aureus treated with H2O2 were notably reduced across the groups. Notably, the predicted promoter regions of the sarA and icaA genes were directly regulated by YycF. Conclusions ASyycG was observed to sensitize biofilm-producing S. aureus to H2O2 intervention synergistically via the sarA and thus may represent a supplementary strategy for managing osteomyelitis. However, future in-depth studies should attempt to replicate our findings in animal models, such as the rat osteomyelitis model. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-021-02218-x.
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Affiliation(s)
- Shizhou Wu
- Department of Orthopedics, West China Hospital, Sichuan University, No.37 Guoxue Alley, Sichuan, 610041, Chengdu, P.R. China
| | - Yunjie Liu
- West China School of Public Health, Sichuan University, Chengdu, China
| | - Lei Lei
- Department of Preventive Dentistry, Hospital of Stomatology, State Key Laboratory of Oral Diseases,, Sichuan University, NO.14 Third Section, Renmin South Road, Sichuan, 610041, Chengdu, P.R. China.
| | - Hui Zhang
- Department of Orthopedics, West China Hospital, Sichuan University, No.37 Guoxue Alley, Sichuan, 610041, Chengdu, P.R. China.
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21
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França A, Gaio V, Lopes N, Melo LDR. Virulence Factors in Coagulase-Negative Staphylococci. Pathogens 2021; 10:170. [PMID: 33557202 PMCID: PMC7913919 DOI: 10.3390/pathogens10020170] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/29/2021] [Accepted: 01/29/2021] [Indexed: 12/13/2022] Open
Abstract
Coagulase-negative staphylococci (CoNS) have emerged as major pathogens in healthcare-associated facilities, being S. epidermidis, S. haemolyticus and, more recently, S. lugdunensis, the most clinically relevant species. Despite being less virulent than the well-studied pathogen S. aureus, the number of CoNS strains sequenced is constantly increasing and, with that, the number of virulence factors identified in those strains. In this regard, biofilm formation is considered the most important. Besides virulence factors, the presence of several antibiotic-resistance genes identified in CoNS is worrisome and makes treatment very challenging. In this review, we analyzed the different aspects involved in CoNS virulence and their impact on health and food.
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Affiliation(s)
- Angela França
- Laboratory of Research in Biofilms Rosário Oliveira, Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal; (V.G.); (N.L.)
| | | | | | - Luís D. R. Melo
- Laboratory of Research in Biofilms Rosário Oliveira, Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal; (V.G.); (N.L.)
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22
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The staphylococcal exopolysaccharide PIA - Biosynthesis and role in biofilm formation, colonization, and infection. Comput Struct Biotechnol J 2020. [PMID: 33240473 DOI: 10.1016/jcsbj202010027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Exopolysaccharide is a key part of the extracellular matrix that contributes to important mechanisms of bacterial pathogenicity, most notably biofilm formation and immune evasion. In the human pathogens Staphylococcus aureus and S. epidermidis, as well as in many other staphylococcal species, the only exopolysaccharide is polysaccharide intercellular adhesin (PIA), a cationic, partially deacetylated homopolymer of N-acetylglucosamine, whose biosynthetic machinery is encoded in the ica locus. PIA production is strongly dependent on environmental conditions and controlled by many regulatory systems. PIA contributes significantly to staphylococcal biofilm formation and immune evasion mechanisms, such as resistance to antimicrobial peptides and ingestion and killing by phagocytes, and presence of the ica genes is associated with infectivity. Due to its role in pathogenesis, PIA has raised considerable interest as a potential vaccine component or target.
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23
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Nguyen HTT, Nguyen TH, Otto M. The staphylococcal exopolysaccharide PIA - Biosynthesis and role in biofilm formation, colonization, and infection. Comput Struct Biotechnol J 2020; 18:3324-3334. [PMID: 33240473 PMCID: PMC7674160 DOI: 10.1016/j.csbj.2020.10.027] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 10/23/2020] [Accepted: 10/25/2020] [Indexed: 12/20/2022] Open
Abstract
PIA is a key extracellular matrix component in staphylococci and other bacteria. PIA is a cationic, partially deacetylated N-acetylglucosamine polymer. PIA has a major role in bacterial biofilms and biofilm-associated infection.
Exopolysaccharide is a key part of the extracellular matrix that contributes to important mechanisms of bacterial pathogenicity, most notably biofilm formation and immune evasion. In the human pathogens Staphylococcus aureus and S. epidermidis, as well as in many other staphylococcal species, the only exopolysaccharide is polysaccharide intercellular adhesin (PIA), a cationic, partially deacetylated homopolymer of N-acetylglucosamine, whose biosynthetic machinery is encoded in the ica locus. PIA production is strongly dependent on environmental conditions and controlled by many regulatory systems. PIA contributes significantly to staphylococcal biofilm formation and immune evasion mechanisms, such as resistance to antimicrobial peptides and ingestion and killing by phagocytes, and presence of the ica genes is associated with infectivity. Due to its role in pathogenesis, PIA has raised considerable interest as a potential vaccine component or target.
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Affiliation(s)
- Hoai T T Nguyen
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, 50 South Drive, Bethesda 20814, MD, USA.,School of Biotechnology, International University, Vietnam National University of Ho Chi Minh City, Khu Pho 6, Thu Duc, Ho Chi Minh City, Viet Nam
| | - Thuan H Nguyen
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, 50 South Drive, Bethesda 20814, MD, USA
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, 50 South Drive, Bethesda 20814, MD, USA
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24
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Schilcher K, Horswill AR. Staphylococcal Biofilm Development: Structure, Regulation, and Treatment Strategies. Microbiol Mol Biol Rev 2020. [PMID: 32792334 DOI: 10.1128/mmbr.00026-19/asset/e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
In many natural and clinical settings, bacteria are associated with some type of biotic or abiotic surface that enables them to form biofilms, a multicellular lifestyle with bacteria embedded in an extracellular matrix. Staphylococcus aureus and Staphylococcus epidermidis, the most frequent causes of biofilm-associated infections on indwelling medical devices, can switch between an existence as single free-floating cells and multicellular biofilms. During biofilm formation, cells first attach to a surface and then multiply to form microcolonies. They subsequently produce the extracellular matrix, a hallmark of biofilm formation, which consists of polysaccharides, proteins, and extracellular DNA. After biofilm maturation into three-dimensional structures, the biofilm community undergoes a disassembly process that leads to the dissemination of staphylococcal cells. As biofilms are dynamic and complex biological systems, staphylococci have evolved a vast network of regulatory mechanisms to modify and fine-tune biofilm development upon changes in environmental conditions. Thus, biofilm formation is used as a strategy for survival and persistence in the human host and can serve as a reservoir for spreading to new infection sites. Moreover, staphylococcal biofilms provide enhanced resilience toward antibiotics and the immune response and impose remarkable therapeutic challenges in clinics worldwide. This review provides an overview and an updated perspective on staphylococcal biofilms, describing the characteristic features of biofilm formation, the structural and functional properties of the biofilm matrix, and the most important mechanisms involved in the regulation of staphylococcal biofilm formation. Finally, we highlight promising strategies and technologies, including multitargeted or combinational therapies, to eradicate staphylococcal biofilms.
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Affiliation(s)
- Katrin Schilcher
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Alexander R Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
- Department of Veterans Affairs Eastern Colorado Health Care System, Denver, Colorado, USA
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25
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Staphylococcal Biofilm Development: Structure, Regulation, and Treatment Strategies. Microbiol Mol Biol Rev 2020; 84:84/3/e00026-19. [PMID: 32792334 DOI: 10.1128/mmbr.00026-19] [Citation(s) in RCA: 283] [Impact Index Per Article: 70.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In many natural and clinical settings, bacteria are associated with some type of biotic or abiotic surface that enables them to form biofilms, a multicellular lifestyle with bacteria embedded in an extracellular matrix. Staphylococcus aureus and Staphylococcus epidermidis, the most frequent causes of biofilm-associated infections on indwelling medical devices, can switch between an existence as single free-floating cells and multicellular biofilms. During biofilm formation, cells first attach to a surface and then multiply to form microcolonies. They subsequently produce the extracellular matrix, a hallmark of biofilm formation, which consists of polysaccharides, proteins, and extracellular DNA. After biofilm maturation into three-dimensional structures, the biofilm community undergoes a disassembly process that leads to the dissemination of staphylococcal cells. As biofilms are dynamic and complex biological systems, staphylococci have evolved a vast network of regulatory mechanisms to modify and fine-tune biofilm development upon changes in environmental conditions. Thus, biofilm formation is used as a strategy for survival and persistence in the human host and can serve as a reservoir for spreading to new infection sites. Moreover, staphylococcal biofilms provide enhanced resilience toward antibiotics and the immune response and impose remarkable therapeutic challenges in clinics worldwide. This review provides an overview and an updated perspective on staphylococcal biofilms, describing the characteristic features of biofilm formation, the structural and functional properties of the biofilm matrix, and the most important mechanisms involved in the regulation of staphylococcal biofilm formation. Finally, we highlight promising strategies and technologies, including multitargeted or combinational therapies, to eradicate staphylococcal biofilms.
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26
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Inhibition of multidrug-resistant foodborne Staphylococcus aureus biofilms by a natural terpenoid (+)-nootkatone and related molecular mechanism. Food Control 2020. [DOI: 10.1016/j.foodcont.2020.107154] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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27
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Shlepotina NM, Peshikova MV, Kolesnikov OL, Shishkova YS. Modern Conceptions about the Mechanisms of Interaction Between Biofilm and Cellular Immunity Factors. ACTA ACUST UNITED AC 2020. [DOI: 10.36233/0372-9311-2020-97-1-83-90] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Features of the cellular immune response in the presence of a microbial biofilm are well described in the literature. Based on numerous studies, it became possible to establish a number of patterns: mature biofilms are better protected from immune factors, the effectiveness of antibiofilm strategies depends on species of the microorganisms, forming the biofilm, and, accordingly, on the composition of the biopolymer matrix. For example, rhamnolipids and alginate of Pseudomonas aeruginosa exert a significant negative effect on the function of immunocompetent cells. The bacteria of biofilms became able to turn to their advantage many of the protective reactions developed by the immune system and fixed evolutionarily, applying them for the growth and development of the microbial consortium.
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28
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Shlepotina NM, Peshikova MV, Kolesnikov OL, Shishkova YS. Modern Conceptions about the Mechanisms of Interaction Between Biofilm and Cellular Immunity Factors. ACTA ACUST UNITED AC 2020. [DOI: 10.36233/0372-9311-2020-1-83-90] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Features of the cellular immune response in the presence of a microbial biofilm are well described in the literature. Based on numerous studies, it became possible to establish a number of patterns: mature biofilms are better protected from immune factors, the effectiveness of antibiofilm strategies depends on species of the microorganisms, forming the biofilm, and, accordingly, on the composition of the biopolymer matrix. For example, rhamnolipids and alginate of Pseudomonas aeruginosa exert a significant negative effect on the function of immunocompetent cells. The bacteria of biofilms became able to turn to their advantage many of the protective reactions developed by the immune system and fixed evolutionarily, applying them for the growth and development of the microbial consortium.
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29
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Yuan Z, Dai Y, Ouyang P, Rehman T, Hussain S, Zhang T, Yin Z, Fu H, Lin J, He C, Lv C, Liang X, Shu G, Song X, Li L, Zou Y, Yin L. Thymol Inhibits Biofilm Formation, Eliminates Pre-Existing Biofilms, and Enhances Clearance of Methicillin-Resistant Staphylococcus aureus (MRSA) in a Mouse Peritoneal Implant Infection Model. Microorganisms 2020; 8:microorganisms8010099. [PMID: 31936809 PMCID: PMC7023310 DOI: 10.3390/microorganisms8010099] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/08/2020] [Accepted: 01/09/2020] [Indexed: 12/19/2022] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a common human pathogen that causes several difficult-to-treat infections, including biofilm-associated infections. The biofilm-forming ability of S. aureus plays a pivotal role in its resistance to most currently available antibiotics, including vancomycin, which is the first-choice drug for treating MRSA infections. In this study, the ability of thymol (a monoterpenoid phenol isolated from plants) to inhibit biofilm formation and to eliminate mature biofilms, was assessed. We found that thymol could inhibit biofilm formation and remove mature biofilms by inhibiting the production of polysaccharide intracellular adhesin (PIA) and the release of extracellular DNA (eDNA). However, cotreatment with thymol and vancomycin was more effective at eliminating MRSA biofilms, in a mouse infection model, than monotherapy with vancomycin. Comparative histopathological analyses revealed that thymol reduced the pathological changes and inflammatory responses in the wounds. Assessments of white blood cell counts and serum TNF-α and IL-6 levels showed reduced inflammation and an increased immune response following treatment with thymol and vancomycin. These results indicate that combinatorial treatment with thymol and vancomycin has the potential to serve as a more effective therapy for MRSA biofilm-associated infections than vancomycin monotherapy.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Lizi Yin
- Correspondence: ; Tel.: +86-170-9284-8186
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30
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Horswill AR, Gordon CP. Structure-Activity Relationship Studies of Small Molecule Modulators of the Staphylococcal Accessory Gene Regulator. J Med Chem 2019; 63:2705-2730. [PMID: 31658413 DOI: 10.1021/acs.jmedchem.9b00798] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The accessory gene regulator (agr) quorum-sensing system is arguably the most important regulator of Staphylococcus virulence. The agr-system serves a crucial role in pathogenesis by triggering substantive gene expression alterations to up-regulate the production of a wide variety of virulence determinants such as exoenzymes (proteases, lipases, nucleases) and downregulate the expression of surface binding proteins. Accordingly, the agr-system represents a compelling target for the development of antivirulence therapeutics as potential adjuncts, or alternatives, to conventional bactericidal and bacteriostatic antibiotics. Despite this potential, to date, no agr-system inhibitors have progressed to the clinic; however, several promising lead compounds have been identified through screens of synthetic and natural product libraries. On the basis of the molecular components within the agr-system, the current contingent of regulating compounds can be clustered into three broad groups, AgrA-P3 activation inhibitors, AgrB-AgrD processing inhibitors, and AgrC-AIP interaction inhibitors. This review aims to provide an overview of the development, structure-activity-relationships, and limitations of compounds within each of these groups in addition to the current opportunities for developing next-generation anologs.
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Affiliation(s)
- Alexander R Horswill
- Veterans Affairs Eastern Colorado Health Care System, Aurora, Colorado 80045, United States.,Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, United States
| | - Christopher P Gordon
- School of Science and Health, Western Sydney University, Locked Bag 1797, Penrith South DC, NSW 2751, Australia.,Molecular Medicine Research Group, School of Medicine, Westerm Sydney University, Building 30, Campbelltown, NSW 2560, Australia
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31
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σ B Inhibits Poly- N-Acetylglucosamine Exopolysaccharide Synthesis and Biofilm Formation in Staphylococcus aureus. J Bacteriol 2019; 201:JB.00098-19. [PMID: 30858304 DOI: 10.1128/jb.00098-19] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 03/07/2019] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus clinical strains are able to produce at least two distinct types of biofilm matrixes: biofilm matrixes made of the polysaccharide intercellular adhesin (PIA) or poly-N-acetylglucosamine (PNAG), whose synthesis is mediated by the icaADBC locus, and biofilm matrixes built of proteins (polysaccharide independent). σB is a conserved alternative sigma factor that regulates the expression of more than 100 genes in response to changes in environmental conditions. While numerous studies agree that σB is required for polysaccharide-independent biofilms, controversy persists over the role of σB in the regulation of PIA/PNAG-dependent biofilm development. Here, we show that genetically unrelated S. aureus σB-deficient strains produced stronger biofilms under both static and flow conditions and accumulated higher levels of PIA/PNAG exopolysaccharide than their corresponding wild-type strains. The increased accumulation of PIA/PNAG in the σB mutants correlated with a greater accumulation of the IcaC protein showed that it was not due to adjustments in icaADBC operon transcription and/or icaADBC mRNA stability. Overall, our results reveal that in the presence of active σB, the turnover of Ica proteins is accelerated, reducing the synthesis of PIA/PNAG exopolysaccharide and consequently the PIA/PNAG-dependent biofilm formation capacity.IMPORTANCE Due to its multifaceted lifestyle, Staphylococcus aureus needs a complex regulatory network to connect environmental signals with cellular physiology. One particular transcription factor, named σB (SigB), is involved in the general stress response and the expression of virulence factors. For many years, great confusion has existed about the role of σB in the regulation of the biofilm lifestyle in S. aureus Our study demonstrated that σB is not necessary for exopolysaccharide-dependent biofilms and, even more, that S. aureus produces stronger biofilms in the absence of σB The increased accumulation of exopolysaccharide correlates with higher stability of the proteins responsible for its synthesis. The present findings reveal an additional regulatory layer to control biofilm exopolysaccharide synthesis under stress conditions.
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32
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Evaluation of Antibacterial Activity of Zataria multiflora Against the Expression of icaADB and aap Gene and Biofilm Formation in Staphylococcus epidermidis. ARCHIVES OF CLINICAL INFECTIOUS DISEASES 2019. [DOI: 10.5812/archcid.65321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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33
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Ong TH, Chitra E, Ramamurthy S, Ling CCS, Ambu SP, Davamani F. Cationic chitosan-propolis nanoparticles alter the zeta potential of S. epidermidis, inhibit biofilm formation by modulating gene expression and exhibit synergism with antibiotics. PLoS One 2019; 14:e0213079. [PMID: 30818374 PMCID: PMC6394969 DOI: 10.1371/journal.pone.0213079] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 02/14/2019] [Indexed: 11/18/2022] Open
Abstract
Staphylococcus epidermidis, is a common microflora of human body that can cause opportunistic infections associated with indwelling devices. It is resistant to multiple antibiotics necessitating the need for naturally occurring antibacterial agents. Malaysian propolis, a natural product obtained from beehives exhibits antimicrobial and antibiofilm properties. Chitosan-propolis nanoparticles (CPNP) were prepared using Malaysian propolis and tested for their effect against S. epidermidis. The cationic nanoparticles depicted a zeta potential of +40 and increased the net electric charge (zeta potential) of S. epidermidis from -17 to -11 mV in a concentration-dependent manner whereas, ethanol (Eth) and ethyl acetate (EA) extracts of propolis further decreased the zeta potential from -17 to -20 mV. Confocal laser scanning microscopy (CLSM) depicted that CPNP effectively disrupted biofilm formation by S. epidermidis and decreased viability to ~25% compared to Eth and EA with viability of ~60-70%. CPNP was more effective in reducing the viability of both planktonic as well as biofilm bacteria compared to Eth and EA. At 100 μg/mL concentration, CPNP decreased the survival of biofilm bacteria by ~70% compared to Eth or EA extracts which decreased viability by only 40%-50%. The morphology of bacterial biofilm examined by scanning electron microscopy depicted partial disruption of biofilm by Eth and EA extracts and significant disruption by CPNP reducing bacterial number in the biofilm by ~90%. Real time quantitative PCR analysis of gene expression in treated bacteria showed that genes involved in intercellular adhesion such as IcaABCD, embp and other related genes were significantly downregulated by CPNP. In addition to having a direct inhibitory effect on the survival of S. epidermidis, CPNP showed synergism with the antibiotics rifampicin, ciprofloxacin, vancomycin and doxycycline suggestive of effective treatment regimens. This would help decrease antibiotic treatment dose by at least 4-fold in combination therapies thereby opening up ways of tackling antibiotic resistance in bacteria.
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Affiliation(s)
- Teik Hwa Ong
- School of Postgraduate Studies, International Medical University, Kuala Lumpur, Malaysia
| | - Ebenezer Chitra
- Division of Applied Biomedical Sciences and Biotechnology, School of Health Sciences, International Medical University, Kuala Lumpur, Malaysia
| | | | | | | | - Fabian Davamani
- Division of Applied Biomedical Sciences and Biotechnology, School of Health Sciences, International Medical University, Kuala Lumpur, Malaysia
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34
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Transcriptional Regulation of icaADBC by both IcaR and TcaR in Staphylococcus epidermidis. J Bacteriol 2019; 201:JB.00524-18. [PMID: 30602488 DOI: 10.1128/jb.00524-18] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 12/17/2018] [Indexed: 12/17/2022] Open
Abstract
S. epidermidis is a primary cause of biofilm-mediated infections in humans due to adherence to foreign bodies. A major staphylococcal biofilm accumulation molecule is polysaccharide intracellular adhesin (PIA), which is synthesized by enzymes encoded by the icaADBC operon. Expression of PIA is highly variable among clinical isolates, suggesting that PIA expression levels are selected in certain niches of the host. However, the mechanisms that govern enhanced icaADBC transcription and PIA synthesis in these isolates are not known. We hypothesized that enhanced PIA synthesis in these isolates was due to function of IcaR and/or TcaR. Thus, two S. epidermidis isolates (1457 and CSF41498) with different icaADBC transcription and PIA expression levels were studied. Constitutive expression of both icaR and tcaR demonstrated that both repressors are functional and can completely repress icaADBC transcription in both 1457 and CSF41498. However, it was found that IcaR was the primary repressor for CSF41498 and TcaR was the primary repressor for 1457. Further analysis demonstrated that icaR transcription was repressed in 1457 in comparison to CSF41498, suggesting that TcaR functions as a repressor only in the absence of IcaR. Indeed, DNase I footprinting suggests IcaR and TcaR may bind to the same site within the icaR-icaA intergenic region. Lastly, we found mutants expressing variable amounts of PIA could rapidly be selected from both 1457 and CSF41498. Collectively, we propose that strains producing enhanced PIA synthesis are selected within certain niches of the host through several genetic mechanisms that function to repress icaR transcription, thus increasing PIA synthesis.IMPORTANCE Staphylococcus epidermidis is a commensal bacterium that resides on our skin. As a commensal, it protects humans from bacterial pathogens through a variety of mechanisms. However, it is also a significant cause of biofilm infections due to its ability to bind to plastic. Polysaccharide intercellular adhesin is a significant component of biofilm, and we propose that the expression of this polysaccharide is beneficial in certain host niches, such as providing extra strength when the bacterium is colonizing the lumen of a catheter, and detrimental in others, such as colonization of the skin surface. We show here that fine-tuning of icaADBC transcription, and thus PIA synthesis, is mediated via two transcriptional repressors, IcaR and TcaR.
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35
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Abstract
Staphylococci, with the leading species Staphylococcus aureus and Staphylococcus epidermidis, are the most frequent causes of infections on indwelling medical devices. The biofilm phenotype that those bacteria adopt during device-associated infection facilitates increased resistance to antibiotics and host immune defenses. This review presents and discusses the molecular mechanisms contributing to staphylococcal biofilm development and their in-vivo importance. Furthermore, it summarizes current strategies for the development of therapeutics against staphylococcal biofilm-associated infection.
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36
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Zheng Y, He L, Asiamah TK, Otto M. Colonization of medical devices by staphylococci. Environ Microbiol 2018; 20:3141-3153. [PMID: 29633455 DOI: 10.1111/1462-2920.14129] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/16/2018] [Accepted: 04/03/2018] [Indexed: 12/19/2022]
Abstract
The use of medical devices in modern medicine is constantly increasing. Despite the multiple precautionary strategies that are being employed in hospitals, which include increased hygiene and sterilization measures, bacterial infections on these devices still happen frequently. Staphylococci are among the major causes of medical device infection. This is mostly due to the strong capacity of those bacteria to form device-associated biofilms, which provide resistance to chemical and physical treatments as well as attacks by the host's immune system. Biofilm development is a multistep process with specific factors participating in each step. It is tightly regulated to provide a balance between biofilm expansion and detachment. Detachment from a biofilm on a medical device can lead to severe systemic infection, such as bacteremia and sepsis. While our understanding of staphylococcal biofilm formation has increased significantly and staphylococcal biofilm formation on medical devices is among the best understood biofilm-associated infections, the extensive effort put in preclinical studies with the goal to find novel therapies against staphylococcal device-associated infections has not yet resulted in efficient, applicable therapeutic options for that difficult-to-treat type of disease.
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Affiliation(s)
- Yue Zheng
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, Bethesda, MD, USA
| | - Lei He
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, Bethesda, MD, USA
| | - Titus K Asiamah
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, Bethesda, MD, USA
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, Bethesda, MD, USA
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37
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Wermser C, Lopez D. Identification of Staphylococcus aureus genes involved in the formation of structured macrocolonies. MICROBIOLOGY-SGM 2018; 164:801-815. [PMID: 29638209 DOI: 10.1099/mic.0.000660] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The human pathogen Staphylococcus aureus causes difficult-to-eradicate biofilm-associated infections that generally become chronic. Understanding the genetic regulation of biofilm formation in S. aureus is central to a precise definition of the conditions and genes involved in development of chronic biofilm-associated infections. Biofilm-related genes have been detected by comparing mutants using the classical submerged biofilm formation assay, in which cells adhere to the bottom of a well containing culture medium. We recently developed an alternative biofilm formation model for S. aureus, based on macrocolony formation on agar plates, comparable to an assay used to study biofilm formation in a few other bacterial species. As organism features are the result of environmental conditions as well as of genes, we used a genome-wide collection of transposon-mapped mutants in this macrocolony assay to seek S. aureus developmental genes and pathways not identified by the classical biofilm formation assay. We identified routes related to glucose and purine metabolism and clarified their regulatory link to macrocolony formation. Our study demonstrates that formation of microbial communities must be correlated to specific growth conditions, and the role of metabolism must be considered in S. aureus biofilm formation and thus, in the development of chronic infections.
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Affiliation(s)
- Charlotte Wermser
- Research Centre for Infectious Diseases (ZINF), University of Würzburg, Würzburg 97080, Germany.,Institute for Molecular Infection Biology (IMIB), University of Würzburg, Würzburg 97080, Germany
| | - Daniel Lopez
- Research Centre for Infectious Diseases (ZINF), University of Würzburg, Würzburg 97080, Germany.,Institute for Molecular Infection Biology (IMIB), University of Würzburg, Würzburg 97080, Germany.,National Centre for Biotechnology, Spanish National Research Council (CNB-CSIC), Madrid 28049, Spain
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Sritharadol R, Hamada M, Kimura S, Ishii Y, Srichana T, Tateda K. Mupirocin at Subinhibitory Concentrations Induces Biofilm Formation in Staphylococcus aureus. Microb Drug Resist 2018; 24:1249-1258. [PMID: 29653478 DOI: 10.1089/mdr.2017.0290] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Mupirocin is a useful antibiotic against superficial skin infections. We compared the impact of mupirocin with a cephalosporin, a fluoroquinolone, an aminoglycoside, and a macrolide on planktonic cell growth and biofilm formation of methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA). MATERIALS AND METHODS Minimum inhibitory concentration (MIC) of mupirocin was determined against S. aureus strains used in this study. Biofilm formation of S. aureus strains exposed to mupirocin was quantified by crystal violet staining assay. Moreover, biofilm structure and viability of the biofilm cells were visualized by Live/Dead staining assay. Biofilm-related gene expression was investigated by quantitative real-time PCR. RESULTS MRSA USA300 clone was resistant to mupirocin with MIC of 1,024 mg/L, while MRSA ATCC-43300 and MSSA ATCC-29213 were susceptible with MICs of 0.03 mg/L. Planktonic cell growth of the S. aureus strains was inhibited by mupirocin in a dose-dependent manner. However, some of the low concentrations of mupirocin less than the MICs promoted biofilm formation. Confocal laser scanning microscopy of the biofilm structures and cell viabilities showed established biofilms of slightly higher cell density in the mupirocin treated groups, especially in the MRSA USA300 clone. Gene expression of RNAIII in planktonic cells and biofilms of MRSA USA300 clone showed the highest upregulation after initial exposure to sub-MIC of mupirocin followed by downregulation, whereas the other antibiotics showed various fluctuations. CONCLUSION The results showed that subinhibitory concentrations of mupirocin promoted biofilm formation of S. aureus, in particular the MRSA USA300 clone.
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Affiliation(s)
- Rutthapol Sritharadol
- 1 Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, Prince of Songkla University , Hat Yai, Songkhla, Thailand .,2 Department of Microbiology and Infectious Diseases, Toho University School of Medicine , Tokyo, Japan
| | - Masakaze Hamada
- 2 Department of Microbiology and Infectious Diseases, Toho University School of Medicine , Tokyo, Japan
| | - Soichiro Kimura
- 2 Department of Microbiology and Infectious Diseases, Toho University School of Medicine , Tokyo, Japan
| | - Yoshikazu Ishii
- 2 Department of Microbiology and Infectious Diseases, Toho University School of Medicine , Tokyo, Japan
| | - Teerapol Srichana
- 1 Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, Prince of Songkla University , Hat Yai, Songkhla, Thailand
| | - Kazuhiro Tateda
- 2 Department of Microbiology and Infectious Diseases, Toho University School of Medicine , Tokyo, Japan
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Costerton JW, Montanaro L, Arciola CR. Biofilm in Implant Infections: Its Production and Regulation. Int J Artif Organs 2018; 28:1062-8. [PMID: 16353112 DOI: 10.1177/039139880502801103] [Citation(s) in RCA: 489] [Impact Index Per Article: 81.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A significant proportion of medical implants become the focus of a device-related infection, difficult to eradicate because bacteria that cause these infections live in well-developed biofilms. Biofilm is a microbial derived sessile community characterized by cells that are irreversibly attached to a substratum or interface to each other, embedded in a matrix of extracellular polymeric substances that they have produced. Bacterial adherence and biofilm production proceed in two steps: first, an attachment to a surface and, second, a cell-to-cell adhesion, with pluristratification of bacteria onto the artificial surface. The first step requires the mediation of bacterial surface proteins, the cardinal of which is similar to S. aureus autolysin and is denominated AtlE. In staphylococci the matrix of extracellular polymeric substances of biofilm is a polymer of β-1,6-linked N-acetylglucosamine (PIA), whose synthesis is mediated by the ica operon. Biofilm formation is partially controlled by quorum sensing, an interbacterial communication mechanism dependent on population density. The principal implants that can be compromised by biofilm associated infections are: central venous catheters, heart valves, ventricular assist devices, coronary stents, neurosurgical ventricular shunts, implantable neurological stimulators, arthro-prostheses, fracture-fixation devices, inflatable penile implants, breast implants, cochlear implants, intra-ocular lenses, dental implants. Biofilms play an important role in the spread of antibiotic resistance. Within the high dense bacterial population, efficient horizontal transfer of resistance and virulence genes takes place. In the future, treatments that inhibit the transcription of biofilm controlling genes might be a successful strategy in inhibiting these infections.
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Affiliation(s)
- J W Costerton
- Center for Biofilms, School of Dentistry, University of Southern California, Los Angeles, California, USA
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40
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Vadyvaloo V, Otto M. Molecular Genetics of Staphylococcus Epidermidis Biofilms on Indwelling Medical Devices. Int J Artif Organs 2018; 28:1069-78. [PMID: 16353113 DOI: 10.1177/039139880502801104] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Staphylococcus epidermidis is an opportunistic pathogen associated with foreign body infections and nosocomial sepsis. The pathogenicity of S. epidermidis is mostly due to its ability to colonize indwelling polymeric devices and form a thick, multilayered biofilm. Biofilm formation is a major problem in treating S. epidermidis infection as biofilms provide significant resistance to antibiotics and to components of the innate host defenses. Various cell surface associated bacterial factors play a role in adherence and accumulation of the biofilm such as the polysaccharide intercellular adhesin and the autolysin AtlE. Furthermore, recent studies have shown that global regulators such as the agr quorum sensing system, the transcriptional regulator sarA and the alternative sigma factor sigB have an important function in the regulation of biofilm formation. Understanding the many complex mechanisms involved in biofilm formation is a key factor in the search for new anti-staphylococcal therapeutics.
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Affiliation(s)
- V Vadyvaloo
- Rocky Mountain Laboratories, NIAID/NIH, Hamilton, MT, USA
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41
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JÄger S, Jonas B, Pfanzelt D, Horstkotte MA, Rohde H, Mack D, Knobloch JKM. Regulation of Biofilm Formation by σB is a Common Mechanism in Staphylococcus Epidermidis and is not Mediated by Transcriptional Regulation of sarA. Int J Artif Organs 2018; 32:584-91. [DOI: 10.1177/039139880903200907] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Biofilm formation is a major pathogenetic factor of Staphylococcus epidermidis. In S. epidermidis the alternative sigma factor σB was identified to regulate biofilm formation in S. epidermidis 1457. In S. aureus σB dependent regulation plays a minor role, whereas sarA (Staphylococcus accessory regulator) is an essential regulator. Therefore, we investigated the impact of σB on sarA transcription and biofilm formation in three independent S. epidermidis isolates. Mutants with dysfunctional σB displayed a strongly reduced biofilm formation, whereas in mutants with constitutive σB activity bio film formation was increased. Transcriptional analysis revealed that IcaA transcription was down-regulated in all σB negative mutants while icaR transcription was up-regulated. However, transcriptional differences varied between individual strains, indicating that additional σB-dependent regulators are involved in biofilm expression. Interestingly, despite the presence of a σB promoter beside two σA promoters no differences, or only minor ones, were observed in sarA transcription, indicating that σB-dependent sarA transcript has no influence on the phenotypic changes. The data observed in independent clinical S. epidermidis isolates suggests that, in contrast to S. aureus, regulation of biofilm formation by σB is a general feature in S. epidermidis. Additionally, we were able to demonstrate that the sarA- dependent regulation is not involved in this regulatory pathway.
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Affiliation(s)
- Sebastian JÄger
- Department of Cardiology and Pneumology, Charité Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin - Germany
| | - Beate Jonas
- Institute for Medical Microbiology and Hygiene, University of Lübeck, Lübeck - Germany
| | - Dorothea Pfanzelt
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg - Germany
| | | | - Holger Rohde
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg - Germany
| | - Dietrich Mack
- Chair of Medical Microbiology and Infectious Diseases, The School of Medicine, University of Wales Swansea, Swansea - United Kingdom
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Costerton WJ, Montanaro L, Balaban N, Arciola CR. Prospecting Gene Therapy of Implant Infections. Int J Artif Organs 2018; 32:689-95. [DOI: 10.1177/039139880903200919] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Infection still represents one of the most serious and ravaging complications associated with prosthetic devices. Staphylococci and enterococci, the bacteria most frequently responsible for orthopedic postsurgical and implant-related infections, express clinically relevant antibiotic resistance. The emergence of antibiotic-resistant bacteria and the slow progress in identifying new classes of antimicrobial agents have encouraged research into novel therapeutic strategies. The adoption of antisense or “antigene” molecules able to silence or knock-out bacterial genes responsible for their virulence is one possible innovative approach. Peptide nucleic acids (PNAs) are potential drug candidates for gene therapy in infections, by silencing a basic gene of bacterial growth or by tackling the antibiotic resistance or virulence factors of a pathogen. An efficacious contrast to bacterial genes should be set up in the first stages of infection in order to prevent colonization of periprosthesis tissues. Genes encoding bacterial factors for adhesion and colonization (biofilm and/or adhesins) would be the best candidates for gene therapy. But after initial enthusiasm for direct antisense knock-out or silencing of essential or virulence bacterial genes, difficulties have emerged; consequently, new approaches are now being attempted. One of these, interference with the regulating system of virulence factors, such as agr, appears particularly promising.
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Affiliation(s)
- William J. Costerton
- Center for Genomic Sciences Allegheny-Singer Research Institute, Pittsburgh, Pennsylvania - USA
| | - Lucio Montanaro
- Research Unit on Implant Infections, Rizzoli Orthopedic Institute, Bologna - Italy
- Experimental Pathology Department, University of Bologna, Bologna - Italy
| | - Naomi Balaban
- Department of Biomedical Sciences, Tufts University Cummings School of Veterinary Medicine, North Grafton, Massachusetts - USA
| | - Carla Renata Arciola
- Research Unit on Implant Infections, Rizzoli Orthopedic Institute, Bologna - Italy
- Experimental Pathology Department, University of Bologna, Bologna - Italy
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Juhlin A, Svensson S, Thomsen P, Trobos M. Staphylococcal biofilm gene expression on biomaterials - A methodological study. J Biomed Mater Res A 2017; 105:3400-3412. [PMID: 28782178 DOI: 10.1002/jbm.a.36171] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 08/01/2017] [Indexed: 01/02/2023]
Abstract
The combination of increased healthcare access, universal aging, and infallible therapy demands, synergistically drive the need for the development of biomaterial technologies that mitigate the challenge of biomaterial-associated infections (BAI). Staphylococcus epidermidis and Staphylococcus aureus account for the majority of BAI due to their ability to accumulate in adherent multilayered biofilm. This investigation details the development of gene expression assays to evaluate the genetic processes of attachment, accumulation, maturation, and dispersal phases of biofilms on biomaterials in vitro, while abiding by the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines. The biofilm formation of S. epidermidis on polyurethane (PU) central venous catheters and S. aureus on machined titanium (Ti) was examined in terms of gene expression at early and late time points. The results provided insight into how each stage of biofilm formation is orchestrated over time on these biomaterials in vitro. Furthermore, the results suggested that mechanical RNA extraction, organic solvents, elimination of genomic DNA, and preamplification are advisable strategies to implement for biofilm gene expression analysis. It is concluded that this method can be employed for the assessment of biofilm-biomaterial interactions at the molecular level. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3400-3412, 2017.
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Affiliation(s)
- Annika Juhlin
- Department of Biomaterials, Sahlgrenska Academy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden.,BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden
| | - Sara Svensson
- Department of Biomaterials, Sahlgrenska Academy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden.,BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden
| | - Peter Thomsen
- Department of Biomaterials, Sahlgrenska Academy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden.,BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden
| | - Margarita Trobos
- Department of Biomaterials, Sahlgrenska Academy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden.,BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden
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44
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Álvarez-Fraga L, Rumbo-Feal S, Pérez A, Gómez MJ, Gayoso C, Vallejo JA, Ohneck EJ, Valle J, Actis LA, Beceiro A, Bou G, Poza M. Global assessment of small RNAs reveals a non-coding transcript involved in biofilm formation and attachment in Acinetobacter baumannii ATCC 17978. PLoS One 2017; 12:e0182084. [PMID: 28763494 PMCID: PMC5538643 DOI: 10.1371/journal.pone.0182084] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 07/12/2017] [Indexed: 12/30/2022] Open
Abstract
Many strains of Acinetobacter baumannii have been described as being able to form biofilm. Small non-coding RNAs (sRNAs) control gene expression in many regulatory circuits in bacteria. The aim of the present work was to provide a global description of the sRNAs produced both by planktonic and biofilm-associated (sessile) cells of A. baumannii ATCC 17978, and to compare the corresponding gene expression profiles to identify sRNAs molecules associated to biofilm formation and virulence. sRNA was extracted from both planktonic and sessile cells and reverse transcribed. cDNA was subjected to 454-pyrosequencing using the GS-FLX Titanium chemistry. The global analysis of the small RNA transcriptome revealed different sRNA expression patterns in planktonic and biofilm associated cells, with some of the transcripts only expressed or repressed in sessile bacteria. A total of 255 sRNAs were detected, with 185 of them differentially expressed in the different types of cells. A total of 9 sRNAs were expressed only in biofilm cells, while the expression of other 21 coding regions were repressed only in biofilm cells. Strikingly, the expression level of the sRNA 13573 was 120 times higher in biofilms than in planktonic cells, an observation that prompted us to further investigate the biological role of this non-coding transcript. Analyses of an isogenic mutant and over-expressing strains revealed that the sRNA 13573 gene is involved in biofilm formation and attachment to A549 human alveolar epithelial cells. The present work serves as a basis for future studies examining the complex regulatory network that regulate biofilm biogenesis and attachment to eukaryotic cells in A. baumannii ATCC 17978.
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Affiliation(s)
- Laura Álvarez-Fraga
- Departamento de Microbiología, Instituto de Investigación Biomédica (INIBIC), Complejo Hospitalario Universitario (CHUAC), A Coruña, Spain
| | - Soraya Rumbo-Feal
- Departamento de Microbiología, Instituto de Investigación Biomédica (INIBIC), Complejo Hospitalario Universitario (CHUAC), A Coruña, Spain
| | - Astrid Pérez
- Departamento de Microbiología, Instituto de Investigación Biomédica (INIBIC), Complejo Hospitalario Universitario (CHUAC), A Coruña, Spain
- Department of Microbiology, Miami University, Oxford, Ohio, United States of America
| | - Manuel J. Gómez
- Department of Molecular Evolution, Center for Astrobiology, INTA-CSIC, Torrejón de Ardoz, Madrid, Spain
- Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, Spain
| | - Carmen Gayoso
- Departamento de Microbiología, Instituto de Investigación Biomédica (INIBIC), Complejo Hospitalario Universitario (CHUAC), A Coruña, Spain
| | - Juan A. Vallejo
- Departamento de Microbiología, Instituto de Investigación Biomédica (INIBIC), Complejo Hospitalario Universitario (CHUAC), A Coruña, Spain
| | - Emily J. Ohneck
- Department of Microbiology, Miami University, Oxford, Ohio, United States of America
| | - Jaione Valle
- Departamento de Biofilms Microbianos, Instituto de Agrobiotecnología, Navarra, Spain
| | - Luis A. Actis
- Department of Microbiology, Miami University, Oxford, Ohio, United States of America
| | - Alejandro Beceiro
- Departamento de Microbiología, Instituto de Investigación Biomédica (INIBIC), Complejo Hospitalario Universitario (CHUAC), A Coruña, Spain
| | - Germán Bou
- Departamento de Microbiología, Instituto de Investigación Biomédica (INIBIC), Complejo Hospitalario Universitario (CHUAC), A Coruña, Spain
- * E-mail: (GB); (MP)
| | - Margarita Poza
- Departamento de Microbiología, Instituto de Investigación Biomédica (INIBIC), Complejo Hospitalario Universitario (CHUAC), A Coruña, Spain
- * E-mail: (GB); (MP)
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Abstract
The staphylococci comprise a diverse genus of Gram-positive, nonmotile commensal organisms that inhabit the skin and mucous membranes of humans and other mammals. In general, staphylococci are benign members of the natural flora, but many species have the capacity to be opportunistic pathogens, mainly infecting individuals who have medical device implants or are otherwise immunocompromised. Staphylococcus aureus and Staphylococcus epidermidis are major sources of hospital-acquired infections and are the most common causes of surgical site infections and medical device-associated bloodstream infections. The ability of staphylococci to form biofilms in vivo makes them highly resistant to chemotherapeutics and leads to chronic diseases. These biofilm infections include osteomyelitis, endocarditis, medical device infections, and persistence in the cystic fibrosis lung. Here, we provide a comprehensive analysis of our current understanding of staphylococcal biofilm formation, with an emphasis on adhesins and regulation, while also addressing how staphylococcal biofilms interact with the immune system. On the whole, this review will provide a thorough picture of biofilm formation of the staphylococcus genus and how this mode of growth impacts the host.
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Xu T, Wu Y, Lin Z, Bertram R, Götz F, Zhang Y, Qu D. Identification of Genes Controlled by the Essential YycFG Two-Component System Reveals a Role for Biofilm Modulation in Staphylococcus epidermidis. Front Microbiol 2017; 8:724. [PMID: 28491057 PMCID: PMC5405149 DOI: 10.3389/fmicb.2017.00724] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 04/07/2017] [Indexed: 01/11/2023] Open
Abstract
Biofilms play a crucial role in the pathogenicity of Staphylococcus epidermidis, while little is known about whether the essential YycFG two-component signal transduction system (TCS) is involved in biofilm formation. We used antisense RNA (asRNA) to silence the yycFG TCS in order to study its regulatory functions in S. epidermidis. Strain 1457 expressing asRNAyycF exhibited a significant delay (~4–5 h) in entry to log phase, which was partially complemented by overexpressing ssaA. The expression of asRNAyycF and asRNAyycG resulted in a 68 and 50% decrease in biofilm formation at 6 h, respectively, while they had no significant inhibitory effect on 12 h biofilm formation. The expression of asRNAyycF led to a ~5-fold increase in polysaccharide intercellular adhesion (PIA) production, but it did not affect the expression of accumulation-associated protein (Aap) or the release of extracellular DNA. Consistently, quantitative real-time PCR showed that silencing yycF resulted in an increased transcription of biofilm-related genes, including icaA, arlR, sarA, sarX, and sbp. An in silico search of the YycF regulon for the conserved YycF recognition pattern and a modified motif in S. epidermidis, along with additional gel shift and DNase I footprinting assays, showed that arlR, sarA, sarX, and icaA are directly regulated by YycF. Our data suggests that YycFG modulates S. epidermidis biofilm formation in an ica-dependent manner.
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Affiliation(s)
- Tao Xu
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Department of Medical Microbiology and Parasitology, Institute of Medical Microbiology and Institutes of Biomedical Sciences, Fudan UniversityShanghai, China.,Key Laboratory of Medical Molecular Virology, Huashan Hospital, Shanghai Medical College of Fudan UniversityShanghai, China
| | - Yang Wu
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Department of Medical Microbiology and Parasitology, Institute of Medical Microbiology and Institutes of Biomedical Sciences, Fudan UniversityShanghai, China
| | - Zhiwei Lin
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Department of Medical Microbiology and Parasitology, Institute of Medical Microbiology and Institutes of Biomedical Sciences, Fudan UniversityShanghai, China
| | - Ralph Bertram
- Klinikum Nürnberg Medical School GmbH, Research Department, Paracelsus Medical UniversityNuremberg, Germany.,Department of Microbial Genetics, Faculty of Science, Interfaculty Institute of Microbiology and Infection Medicine Tübingen, University of TübingenTübingen, Germany
| | - Friedrich Götz
- Department of Microbial Genetics, Faculty of Science, Interfaculty Institute of Microbiology and Infection Medicine Tübingen, University of TübingenTübingen, Germany
| | - Ying Zhang
- Key Laboratory of Medical Molecular Virology, Huashan Hospital, Shanghai Medical College of Fudan UniversityShanghai, China.,Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins UniversityBaltimore, MD, USA
| | - Di Qu
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Department of Medical Microbiology and Parasitology, Institute of Medical Microbiology and Institutes of Biomedical Sciences, Fudan UniversityShanghai, China
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Ferrer M, Rodriguez J, Álvarez L, Artacho A, Royo G, Mira A. Effect of antibiotics on biofilm inhibition and induction measured by real-time cell analysis. J Appl Microbiol 2017; 122:640-650. [DOI: 10.1111/jam.13368] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 11/18/2016] [Accepted: 11/28/2016] [Indexed: 12/28/2022]
Affiliation(s)
- M.D. Ferrer
- FISABIO Foundation; Centre for Advanced Research in Public Health; Valencia Spain
| | | | - L. Álvarez
- Hospital General Universitario; Elche Spain
| | - A. Artacho
- FISABIO Foundation; Centre for Advanced Research in Public Health; Valencia Spain
| | - G. Royo
- Hospital General Universitario; Elche Spain
| | - A. Mira
- FISABIO Foundation; Centre for Advanced Research in Public Health; Valencia Spain
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A Novel Repressor of the ica Locus Discovered in Clinically Isolated Super-Biofilm-Elaborating Staphylococcus aureus. mBio 2017; 8:mBio.02282-16. [PMID: 28143981 PMCID: PMC5285506 DOI: 10.1128/mbio.02282-16] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Staphylococcus aureus TF2758 is a clinical isolate from an atheroma and a super-biofilm-elaborating/polysaccharide intercellular adhesin (PIA)/poly-N-acetylglucosamine (PNAG)-overproducing strain (L. Shrestha et al., Microbiol Immunol 60:148–159, 2016, https://doi.org/10.1111/1348-0421.12359). A microarray analysis and DNA genome sequencing were performed to identify the mechanism underlying biofilm overproduction by TF2758. We found high transcriptional expression levels of a 7-gene cluster (satf2580 to satf2586) and the ica operon in TF2758. Within the 7-gene cluster, a putative transcriptional regulator gene designated rob had a nonsense mutation that caused the truncation of the protein. The complementation of TF2758 with rob from FK300, an rsbU-repaired derivative of S. aureus strain NCTC8325-4, significantly decreased biofilm elaboration, suggesting a role for rob in this process. The deletion of rob in non-biofilm-producing FK300 significantly increased biofilm elaboration and PIA/PNAG production. In the search for a gene(s) in the 7-gene cluster for biofilm elaboration controlled by rob, we identified open reading frame (ORF) SAOUHSC_2898 (satf2584). Our results suggest that ORF SAOUHSC_2898 (satf2584) and icaADBC are required for enhanced biofilm elaboration and PIA/PNAG production in the rob deletion mutant. Rob bound to a palindromic sequence within its own promoter region. Furthermore, Rob recognized the TATTT motif within the icaR-icaA intergenic region and bound to a 25-bp DNA stretch containing this motif, which is a critically important short sequence regulating biofilm elaboration in S. aureus. Our results strongly suggest that Rob is a long-sought repressor that recognizes and binds to the TATTT motif and is an important regulator of biofilm elaboration through its control of SAOUHSC_2898 (SATF2584) and Ica protein expression in S. aureus. During the search for molecular mechanisms underlying biofilm overproduction of Staphylococcus aureus TF2758, we found a putative transcriptional regulator gene designated rob within a 7-gene cluster showing a high transcriptional expression level by microarray analysis. The deletion of rob in non-biofilm-producing FK300, an rsbU-repaired derivative of NCTC8325-4, significantly increased biofilm elaboration and PIA/PNAG production. The search for a gene(s) in the 7-gene cluster for biofilm elaboration controlled by rob identified ORF SAOUHSC_2898. Besides binding to its own promoter region to control ORF SAOUHSC_2898 expression, Rob recognized the TATTT motif within the icaR-icaA intergenic region and bound to a 25-bp DNA stretch containing this motif, which is a critically important short sequence regulating biofilm elaboration in S. aureus. Our results strongly suggest that Rob is a long-sought repressor that recognizes and binds to the TATTT motif and is a new important regulator of biofilm elaboration through its control of SAOUHSC_2898 and Ica protein expression in S. aureus.
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Paharik AE, Kotasinska M, Both A, Hoang TMN, Büttner H, Roy P, Fey PD, Horswill AR, Rohde H. The metalloprotease SepA governs processing of accumulation-associated protein and shapes intercellular adhesive surface properties in Staphylococcus epidermidis. Mol Microbiol 2017; 103:860-874. [PMID: 27997732 DOI: 10.1111/mmi.13594] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/01/2016] [Indexed: 12/11/2022]
Abstract
The otherwise harmless skin inhabitant Staphylococcus epidermidis is a major cause of healthcare-associated medical device infections. The species' selective pathogenic potential depends on its production of surface adherent biofilms. The Cell wall-anchored protein Aap promotes biofilm formation in S. epidermidis, independently from the polysaccharide intercellular adhesin PIA. Aap requires proteolytic cleavage to act as an intercellular adhesin. Whether and which staphylococcal proteases account for Aap processing is yet unknown. Here, evidence is provided that in PIA-negative S. epidermidis 1457Δica, the metalloprotease SepA is required for Aap-dependent S. epidermidis biofilm formation in static and dynamic biofilm models. qRT-PCR and protease activity assays demonstrated that under standard growth conditions, sepA is repressed by the global regulator SarA. Inactivation of sarA increased SepA production, and in turn augmented biofilm formation. Genetic and biochemical analyses demonstrated that SepA-related induction of biofilm accumulation resulted from enhanced Aap processing. Studies using recombinant proteins demonstrated that SepA is able to cleave the A domain of Aap at residue 335 and between the A and B domains at residue 601. This study identifies the mechanism behind Aap-mediated biofilm maturation, and also demonstrates a novel role for a secreted staphylococcal protease as a requirement for the development of a biofilm.
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Affiliation(s)
- Alexandra E Paharik
- Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Marta Kotasinska
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Anna Both
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Tra-My N Hoang
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Henning Büttner
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Paroma Roy
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Paul D Fey
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Alexander R Horswill
- Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Holger Rohde
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
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He HJ, Sun FJ, Wang Q, Liu Y, Xiong LR, Xia PY. Erythromycin resistance features and biofilm formation affected by subinhibitory erythromycin in clinical isolates of Staphylococcus epidermidis. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2016; 49:33-40. [DOI: 10.1016/j.jmii.2014.03.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 01/20/2014] [Accepted: 03/05/2014] [Indexed: 11/16/2022]
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