1
|
Atasoy M, Bartkova S, Çetecioğlu-Gürol Z, P Mira N, O'Byrne C, Pérez-Rodríguez F, Possas A, Scheler O, Sedláková-Kaduková J, Sinčák M, Steiger M, Ziv C, Lund PA. Methods for studying microbial acid stress responses: from molecules to populations. FEMS Microbiol Rev 2024; 48:fuae015. [PMID: 38760882 PMCID: PMC11418653 DOI: 10.1093/femsre/fuae015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 03/27/2024] [Accepted: 05/16/2024] [Indexed: 05/20/2024] Open
Abstract
The study of how micro-organisms detect and respond to different stresses has a long history of producing fundamental biological insights while being simultaneously of significance in many applied microbiological fields including infection, food and drink manufacture, and industrial and environmental biotechnology. This is well-illustrated by the large body of work on acid stress. Numerous different methods have been used to understand the impacts of low pH on growth and survival of micro-organisms, ranging from studies of single cells to large and heterogeneous populations, from the molecular or biophysical to the computational, and from well-understood model organisms to poorly defined and complex microbial consortia. Much is to be gained from an increased general awareness of these methods, and so the present review looks at examples of the different methods that have been used to study acid resistance, acid tolerance, and acid stress responses, and the insights they can lead to, as well as some of the problems involved in using them. We hope this will be of interest both within and well beyond the acid stress research community.
Collapse
Affiliation(s)
- Merve Atasoy
- UNLOCK, Wageningen University and Research, PO Box 9101, 6700 HB, the Netherlands
| | - Simona Bartkova
- Department of Chemistry and Biotechnology, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia
| | - Zeynep Çetecioğlu-Gürol
- Department of Industrial Biotechnology, KTH Royal Institute of Technology, Roslagstullsbacken 21 106 91 Stockholm, Stockholm, Sweden
| | - Nuno P Mira
- iBB, Institute for Bioengineering and Biosciences, Department of Bioengineering, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Conor O'Byrne
- Microbiology, School of Biological and Chemical Sciences, University of Galway, University Road, Galway, H91 TK33, Ireland
| | - Fernando Pérez-Rodríguez
- Department of Food Science and Tehcnology, UIC Zoonosis y Enfermedades Emergentes ENZOEM, University of Córdoba, 14014 Córdoba, Spain
| | - Aricia Possas
- Department of Food Science and Tehcnology, UIC Zoonosis y Enfermedades Emergentes ENZOEM, University of Córdoba, 14014 Córdoba, Spain
| | - Ott Scheler
- Department of Chemistry and Biotechnology, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia
| | - Jana Sedláková-Kaduková
- Institute of Chemistry and Environmental Sciences, University of Ss. Cyril and Methodius, 91701 Trnava, Republic of Slovakia
| | - Mirka Sinčák
- Institute of Chemistry and Environmental Sciences, University of Ss. Cyril and Methodius, 91701 Trnava, Republic of Slovakia
| | - Matthias Steiger
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Getreidemarkt 9, 1060 Vienna, Austria
| | - Carmit Ziv
- Department of Postharvest Science, Agricultural Research Organization, Volcani Center, 7505101 Rishon LeZion, Israel
| | - Peter A Lund
- School of Biosciences and Institute of Microbiology of Infection, University of Birmingham, Birmingham B15 2TT, United Kingdom
| |
Collapse
|
2
|
Maureira A, Zapata M, Olave J, Jeison D, Wong LS, Panico A, Hernández P, Cisternas LA, Rivas M. MICP mediated by indigenous bacteria isolated from tailings for biocementation for reduction of wind erosion. Front Bioeng Biotechnol 2024; 12:1393334. [PMID: 38938979 PMCID: PMC11208896 DOI: 10.3389/fbioe.2024.1393334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 05/23/2024] [Indexed: 06/29/2024] Open
Abstract
In this study, native ureolytic bacteria were isolated from copper tailings soils to perform microbial-induced carbonate precipitation (MICP) tests and evaluate their potential for biocement formation and their contribution to reduce the dispersion of particulate matter into the environment from tailings containing potentially toxic elements. It was possible to isolate a total of 46 bacteria; among them only three showed ureolytic activity: Priestia megaterium T130-1, Paenibacillus sp. T130-13 and Staphylococcus sp. T130-14. Biocement cores were made by mixing tailings with the isolated bacteria in presence of urea, resulting similar to those obtained with Sporosarcina pasteurii and Bacillus subtilis used as positive control. Indeed, XRD analysis conducted on biocement showed the presence of microcline (B. subtilis 17%; P. megaterium 11. 9%), clinochlore (S. pasteurii, 6.9%) and magnesiumhornblende (Paenibacillus sp. 17.8%; P. megaterium 14.6%); all these compounds were not initially present in the tailings soils. Moreover the presence of calcite (control 0.828%; Paenibacillus sp. 5.4%) and hematite (control 0.989%; B. subtilis 6.4%) was also significant unlike the untreated control. The development of biofilms containing abundant amount of Ca, C, and O on microscopic soil particles was evidenced by means of FE-SEM-EDX and XRD. Wind tunnel tests were carried out to investigate the resistance of biocement samples, accounted for a mass loss five holds lower than the control, i.e., the rate of wind erosion in the control corresponded to 82 g/m2h while for the biocement treated with Paenibacillus sp. it corresponded to only 16.371 g/m2h. Finally, in compression tests, the biocement samples prepared with P. megaterium (28.578 psi) and Paenibacillus sp. (28.404 psi) showed values similar to those obtained with S. pasteurii (27.102 psi), but significantly higher if compared to the control (15.427 psi), thus improving the compression resistance capacity of the samples by 85.2% and 84.1% with respect to the control. According to the results obtained, the biocement samples generated with the native strains showed improvements in the mechanical properties of the soil supporting them as potential candidates in applications for the stabilization of mining liabilities in open environments using bioaugmentation strategies with native strains isolated from the same mine tailing.
Collapse
Affiliation(s)
- Alejandro Maureira
- Laboratorio de Biotecnología Ambiental Aplicada BIOAL, Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
| | - Manuel Zapata
- Laboratorio de Biotecnología Ambiental Aplicada BIOAL, Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
| | - Jorge Olave
- Laboratorio de Biotecnología Ambiental Aplicada BIOAL, Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
| | - David Jeison
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Liey-Si Wong
- Centro Lithium I+D+i Universidad Católica del Norte, Antofagasta, Chile
| | - Antonio Panico
- Department of Engineering, University of Campania L. Vanvitelli, Aversa, Italy
| | - Pía Hernández
- Departamento de Ingeniería Química y Procesos de Minerales, Facultad de Ingeniería, Universidad de Antofagasta, Antofagasta, Chile
| | - Luis A. Cisternas
- Departamento de Ingeniería Química y Procesos de Minerales, Facultad de Ingeniería, Universidad de Antofagasta, Antofagasta, Chile
| | - Mariella Rivas
- Laboratorio de Biotecnología Ambiental Aplicada BIOAL, Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
| |
Collapse
|
3
|
Wang Y, Dong W, Chu L, Zhao H, He L, Sheng X. A combination of proteomics, genetics, and physiology provides insights into the acid-tolerance phenotype of Pseudomonas pergaminensis F77. Microbiol Res 2024; 278:127545. [PMID: 37952350 DOI: 10.1016/j.micres.2023.127545] [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: 09/13/2023] [Revised: 10/29/2023] [Accepted: 11/04/2023] [Indexed: 11/14/2023]
Abstract
Acid tolerance is crucial for the effective and persistent mineral weathering by acid-producing bacteria. Here, the molecular basis of the acid tolerance of mineral-weathering Pseudomonas pergaminensis F77 was identified using proteomics analysis of the strain under acid stress. Then, the acid tolerance of strain F77 and its mutants with deletion of the acid tolerance-related genes orf03767, mcp, resR, nueR, yegD, and fxsA, which are involved in the two-component systems, DNA repair, nucleotide binding, and membrane parts, were compared. Finally, the acid tolerance-related physiological mechanisms of strain F77 and its mutants F77ΔnueR and F77ΔresR under acidic conditions were characterized. The significantly upregulated proteins in the acid-adapted and acid-challenged strain F77 included the proteins involved in metabolic pathways associated with ATPase, membrane components, organic acid transmembrane transporters, response to stimulus, nucleotide binding, ABC transporters, and two-component systems. The cell numbers decreased by 24-100% at pH ≤ 4.50, while the membrane fluidity increased by 22-61% at pH ≤ 5.50 for the mutants F77ΔnueR and F77ΔresR, compared with that of strain F77. The intracellular H+-ATPase activities decreased by 29-33% for the mutant F77ΔnueR at pH ≤ 4.50% and 33-79% for the mutant F77ΔresR at all tested pHs (pH ≤ 7.00); meanwhile, the ratios of intracellular NAD+/NADH decreased by 71-91% for the mutant F77ΔresR at all tested pHs (pH ≤ 7.00), compared with that of strain F77. Furthermore, the intracellular putrescine concentrations were reduced by 40-70% for the mutant F77ΔresR at all tested pHs (pH ≤ 7.00) compared with that of strain F77. Our findings suggested that multiple proteins and metabolic pathways were associated with bacterial acid tolerance and revealed that nueR and resR were involved in acid tolerance based on their modulation of multiple acid tolerance-related physiological functions in strain F77.
Collapse
Affiliation(s)
- Yuanli Wang
- College of Life Sciences, Nanjing Agricultural University, Nanjing, China; College of Biological and Food Engineering, Anhui Polytechnic University, Wuhu, China
| | - Wen Dong
- College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Lingfeng Chu
- College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Hui Zhao
- College of Life Sciences, Nanjing Agricultural University, Nanjing, China
| | - Linyan He
- College of Life Sciences, Nanjing Agricultural University, Nanjing, China.
| | - Xiafang Sheng
- College of Life Sciences, Nanjing Agricultural University, Nanjing, China.
| |
Collapse
|
4
|
Beetham CM, Schuster CF, Kviatkovski I, Santiago M, Walker S, Gründling A. Histidine transport is essential for the growth of Staphylococcus aureus at low pH. PLoS Pathog 2024; 20:e1011927. [PMID: 38227607 PMCID: PMC10817146 DOI: 10.1371/journal.ppat.1011927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 01/26/2024] [Accepted: 12/28/2023] [Indexed: 01/18/2024] Open
Abstract
Staphylococcus aureus is an opportunistic pathogen capable of causing many different human diseases. During colonization and infection, S. aureus will encounter a range of hostile environments, including acidic conditions such as those found on the skin and within macrophages. However, little is known about the mechanisms that S. aureus uses to detect and respond to low pH. Here, we employed a transposon sequencing approach to determine on a genome-wide level the genes required or detrimental for growth at low pH. We identified 31 genes that were essential for the growth of S. aureus at pH 4.5 and confirmed the importance of many of them through follow up experiments using mutant strains inactivated for individual genes. Most of the genes identified code for proteins with functions in cell wall assembly and maintenance. These data suggest that the cell wall has a more important role than previously appreciated in promoting bacterial survival when under acid stress. We also identified several novel processes previously not linked to the acid stress response in S. aureus. These include aerobic respiration and histidine transport, the latter by showing that one of the most important genes, SAUSA300_0846, codes for a previously uncharacterized histidine transporter. We further show that under acid stress, the expression of the histidine transporter gene is increased in WT S. aureus. In a S. aureus SAUSA300_0846 mutant strain expression of the histidine biosynthesis genes is induced under acid stress conditions allowing the bacteria to maintain cytosolic histidine levels. This strain is, however, unable to maintain its cytosolic pH to the same extent as a WT strain, revealing an important function specifically for histidine transport in the acid stress response of S. aureus.
Collapse
Affiliation(s)
- Catrin M. Beetham
- Section of Molecular Microbiology and Centre for Bacterial Resistance Biology, Imperial College London, London, United Kingdom
| | - Christopher F. Schuster
- Section of Molecular Microbiology and Centre for Bacterial Resistance Biology, Imperial College London, London, United Kingdom
| | - Igor Kviatkovski
- Section of Molecular Microbiology and Centre for Bacterial Resistance Biology, Imperial College London, London, United Kingdom
| | - Marina Santiago
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Suzanne Walker
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Angelika Gründling
- Section of Molecular Microbiology and Centre for Bacterial Resistance Biology, Imperial College London, London, United Kingdom
| |
Collapse
|
5
|
Lee JI, Kim SS, Kang DH. Characteristics of Staphylococcus aureus biofilm matured in tryptic soy broth, low-fat milk, or whole milk samples along with inactivation by 405 nm light combined with folic acid. Food Microbiol 2023; 116:104350. [PMID: 37689424 DOI: 10.1016/j.fm.2023.104350] [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: 12/27/2022] [Revised: 07/30/2023] [Accepted: 08/02/2023] [Indexed: 09/11/2023]
Abstract
In the present study, the characteristics of Staphylococcus aureus biofilms matured in tryptic soy broth (TSB), low-fat milk, or whole milk samples were identified along with their resistance to 405 nm light with or without folic acid. Phenotypic properties of carbohydrate and protein contents in extracellular polymeric substance (EPS) of S. aureus biofilms matured in different conditions were identified. The carbohydrate content was higher in the biofilm matured in low-fat milk (1.27) than the samples matured in whole milk (0.58) and TSB (0.10). Protein content in the EPS of biofilm was higher in the sample matured in whole milk (6.59) than the samples matured in low-fat milk (3.24) and TSB (2.08). Moreover, the maturation condition had a significant effect on the membrane lipid composition of the biofilm, producing more unsaturated fatty acids in biofilm matured in milk samples. These changes in biofilm matured in milk samples increased the resistance of S. aureus to 405 nm light in the presence of folic acid (LFA). Additionally, transcriptomic analysis was conducted to identify the response of S. aureus biofilm to LFA treatment. Several genes related to DNA and protein protection from oxidative stress along with biofilm accumulation were overexpressed in the LFA-treated biofilms. These results indicate the maturation of S. aureus biofilm in various samples and the biofilms responses to bactericidal treatments.
Collapse
Affiliation(s)
- Jae-Ik Lee
- Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Center for Food and Bioconvergence, Research Institute for Agricultural and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea; Institutes of Green Bio Science & Technology, Seoul National University, Pyeongchang-gun, Gangwon-do, 25354, Republic of Korea
| | - Sang-Soon Kim
- Department of Food Engineering, Dankook University, Cheonan, Chungnam, 31116, Republic of Korea
| | - Dong-Hyun Kang
- Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Center for Food and Bioconvergence, Research Institute for Agricultural and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea; Institutes of Green Bio Science & Technology, Seoul National University, Pyeongchang-gun, Gangwon-do, 25354, Republic of Korea.
| |
Collapse
|
6
|
Deng Y, Zang S, Lin Z, Xu L, Cheng C, Feng J. The Pleiotropic Phenotypes Caused by an hfq Null Mutation in Vibrio harveyi. Microorganisms 2023; 11:2741. [PMID: 38004752 PMCID: PMC10672845 DOI: 10.3390/microorganisms11112741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 11/08/2023] [Accepted: 11/08/2023] [Indexed: 11/26/2023] Open
Abstract
Hfq is a global regulator and can be involved in multiple cellular processes by assisting small regulatory RNAs (sRNAs) to target mRNAs. To gain insight into the virulence regulation of Hfq in Vibrio harveyi, the hfq null mutant, ∆hfq, was constructed in V. harveyi strain 345. Compared with the wild-type strain, the mortality of pearl gentian sharply declined from 80% to 0% in ∆hfq when infected with a dose that was 7.5-fold the median lethal dose (LD50). Additionally, ∆hfq led to impairments of bacterial growth, motility, and biofilm formation and resistance to reactive oxygen species, chloramphenicol, and florfenicol. A transcriptome analysis indicated that the expression of 16.39% genes on V. harveyi 345 were significantly changed after the deletion of hfq. Without Hfq, the virulence-related pathways, including flagellar assembly and bacterial chemotaxis, were repressed. Moreover, eleven sRNAs, including sRNA0405, sRNA0078, sRNA0419, sRNA0145, and sRNA0097, which, respectively, are involved in chloramphenicol/florfenicol resistance, outer membrane protein synthesis, electron transport, amino acid metabolism, and biofilm formation, were significantly down-regulated. In general, Hfq contributes to the virulence of V. harveyi 345 probably via positively regulating bacterial motility and biofilm formation. It is involved in flagellar assembly and bacterial chemotaxis by binding sRNAs and regulating the target mRNAs.
Collapse
Affiliation(s)
| | | | | | | | | | - Juan Feng
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; (Y.D.); (S.Z.); (Z.L.); (L.X.); (C.C.)
| |
Collapse
|
7
|
Loi VV, Busche T, Kuropka B, Müller S, Methling K, Lalk M, Kalinowski J, Antelmann H. Staphylococcus aureus adapts to the immunometabolite itaconic acid by inducing acid and oxidative stress responses including S-bacillithiolations and S-itaconations. Free Radic Biol Med 2023; 208:859-876. [PMID: 37793500 DOI: 10.1016/j.freeradbiomed.2023.09.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/21/2023] [Accepted: 09/26/2023] [Indexed: 10/06/2023]
Abstract
Staphylococcus aureus is a major pathogen, which has to defend against reactive oxygen and electrophilic species encountered during infections. Activated macrophages produce the immunometabolite itaconate as potent electrophile and antimicrobial upon pathogen infection. In this work, we used transcriptomics, metabolomics and shotgun redox proteomics to investigate the specific stress responses, metabolic changes and redox modifications caused by sublethal concentrations of itaconic acid in S. aureus. In the RNA-seq transcriptome, itaconic acid caused the induction of the GlnR, KdpDE, CidR, SigB, GraRS, PerR, CtsR and HrcA regulons and the urease-encoding operon, revealing an acid and oxidative stress response and impaired proteostasis. Neutralization using external urea as ammonium source improved the growth and decreased the expression of the glutamine synthetase-controlling GlnR regulon, indicating that S. aureus experienced ammonium starvation upon itaconic acid stress. In the extracellular metabolome, the amounts of acetate and formate were decreased, while secretion of pyruvate and the neutral product acetoin were strongly enhanced to avoid intracellular acidification. Exposure to itaconic acid affected the amino acid uptake and metabolism as revealed by the strong intracellular accumulation of lysine, threonine, histidine, aspartate, alanine, valine, leucine, isoleucine, cysteine and methionine. In the proteome, itaconic acid caused widespread S-bacillithiolation and S-itaconation of redox-sensitive antioxidant and metabolic enzymes, ribosomal proteins and translation factors in S. aureus, supporting its oxidative and electrophilic mode of action in S. aureus. In phenotype analyses, the catalase KatA, the low molecular weight thiol bacillithiol and the urease provided protection against itaconic acid-induced oxidative and acid stress in S. aureus. Altogether, our results revealed that under physiological infection conditions, such as in the acidic phagolysome, itaconic acid is a highly effective antimicrobial against multi-resistant S. aureus isolates, which acts as weak acid causing an acid, oxidative and electrophilic stress response, leading to S-bacillithiolation and itaconation.
Collapse
Affiliation(s)
- Vu Van Loi
- Freie Universität Berlin, Institute of Biology-Microbiology, D-14195, Berlin, Germany
| | - Tobias Busche
- Microbial Genomics and Biotechnology, Center for Biotechnology, Bielefeld University, D-33615, Bielefeld, Germany
| | - Benno Kuropka
- Freie Universität Berlin, Institute of Chemistry and Biochemistry, D-14195, Berlin, Germany
| | - Susanne Müller
- Freie Universität Berlin, Institute of Biology-Microbiology, D-14195, Berlin, Germany
| | - Karen Methling
- Department of Cellular Biochemistry and Metabolomics, University of Greifswald, 17487, Greifswald, Germany
| | - Michael Lalk
- Department of Cellular Biochemistry and Metabolomics, University of Greifswald, 17487, Greifswald, Germany
| | - Jörn Kalinowski
- Microbial Genomics and Biotechnology, Center for Biotechnology, Bielefeld University, D-33615, Bielefeld, Germany
| | - Haike Antelmann
- Freie Universität Berlin, Institute of Biology-Microbiology, D-14195, Berlin, Germany.
| |
Collapse
|
8
|
Gehrke AKE, Giai C, Gómez MI. Staphylococcus aureus Adaptation to the Skin in Health and Persistent/Recurrent Infections. Antibiotics (Basel) 2023; 12:1520. [PMID: 37887220 PMCID: PMC10604630 DOI: 10.3390/antibiotics12101520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/28/2023] Open
Abstract
Staphylococcus aureus is a microorganism with an incredible capability to adapt to different niches within the human body. Approximately between 20 and 30% of the population is permanently but asymptomatically colonized with S. aureus in the nose, and another 30% may carry S. aureus intermittently. It has been established that nasal colonization is a risk factor for infection in other body sites, including mild to severe skin and soft tissue infections. The skin has distinct features that make it a hostile niche for many bacteria, therefore acting as a strong barrier against invading microorganisms. Healthy skin is desiccated; it has a low pH at the surface; the upper layer is constantly shed to remove attached bacteria; and several host antimicrobial peptides are produced. However, S. aureus is able to overcome these defenses and colonize this microenvironment. Moreover, this bacterium can very efficiently adapt to the stressors present in the skin under pathological conditions, as it occurs in patients with atopic dermatitis or suffering chronic wounds associated with diabetes. The focus of this manuscript is to revise the current knowledge concerning how S. aureus adapts to such diverse skin conditions causing persistent and recurrent infections.
Collapse
Affiliation(s)
- Ana-Katharina E. Gehrke
- Centro de Estudios Biomédicos, Básicos, Aplicados y Desarrollo (CEBBAD), Departamento de Investigaciones Biomédicas y Biotecnológicas, Universidad Maimónides, Buenos Aires C1405BCK, Argentina;
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1425FQB, Argentina
| | - Constanza Giai
- Instituto de Histología y Embriología de Mendoza, Universidad Nacional de Cuyo—(UNCuyo) CONICET, Mendoza M5502JMA, Argentina;
- Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza M5502JMA, Argentina
- Facultad de Farmacia y Bioquímica, Universidad Juan Agustín Maza, Mendoza C1006ACC, Argentina
| | - Marisa I. Gómez
- Centro de Estudios Biomédicos, Básicos, Aplicados y Desarrollo (CEBBAD), Departamento de Investigaciones Biomédicas y Biotecnológicas, Universidad Maimónides, Buenos Aires C1405BCK, Argentina;
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1425FQB, Argentina
- Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires C1121A6B, Argentina
| |
Collapse
|
9
|
Siddiqui H, Atia-Tul-Wahab, Ahmed A, Choudhary MI. Structural and Functional Analysis of Urease Accessory Protein E from Vancomycin-Resistance Staphylococcus aureus MU50 Strain. Protein Pept Lett 2023; 30:754-762. [PMID: 37533244 DOI: 10.2174/0929866530666230801163340] [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: 02/23/2023] [Revised: 05/10/2023] [Accepted: 06/23/2023] [Indexed: 08/04/2023]
Abstract
BACKGROUND An increasing prevalence of biofilm forming strains by vancomycinresistance Staphylococcus aureus (VRSA) is one of the most important causes of antimicrobial resistance. VRSA possesses various regulatory factors to form and sustain biofilm in biotic or abiotic conditions. Among them, ureolytic activity is an important factor in the stabilization of biofilms by neutralizing the acidic environment. Various urease accessory proteins are required to activate the urease enzyme inside the biofilm. OBJECTIVE To optimize the cloning, expression and purification of urease accessory protein E from VRSA for determination of the secondary structure, and functional characterization by using Berthelot's method. METHODS BAB58453.1 gene (which encodes possible urease accessory protein E), having 38% similarity to Bacillus pasteurii UreE protein, was cloned, expressed, and purified by single-step affinity chromatography for performing secondary structural studies using circular dichroism spectroscopy, and functional analysis using Berthelot's and crystal violet assay. RESULTS Structure elucidation using NMR and circular dichroism spectroscopy techniques revealed that UreE protein has a partially foldedα-helical structure. Using Berthelot's method, it was identified that the purified UreE protein has enhanced urease enzyme activity, in comparison to the control. From the results of Berthelot's and crystal violet assays, it was deduced that the selected gene (UreE protein) plays a key role in enhancing urease enzyme activity and contributes to biofilm stability. CONCLUSION Structural studies on VRSA urease accessory proteins could aid in the identification of new drug targets or the development of effective antibiofilm strategies (in combination with other drug targets) against infections caused by biofilm-producing strains.
Collapse
Affiliation(s)
- Humaira Siddiqui
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi-75270, Pakistan
| | - Atia-Tul-Wahab
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi-75270, Pakistan
| | - Aftab Ahmed
- School of Pharmacy, Chapman University, Irvine, CA 92618, USA
| | - M Iqbal Choudhary
- H.E.J. Research-Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah-21412, Saudi Arabia
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi-75270, Pakistan
| |
Collapse
|
10
|
Chong CE, Bengtsson RJ, Horsburgh MJ. Comparative genomics of Staphylococcus capitis reveals species determinants. Front Microbiol 2022; 13:1005949. [PMID: 36246238 PMCID: PMC9563023 DOI: 10.3389/fmicb.2022.1005949] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 09/05/2022] [Indexed: 11/27/2022] Open
Abstract
Staphylococcus capitis is primarily described as a human skin commensal but is now emergent as an opportunistic pathogen isolated from the bloodstream and prosthetic joint infections, and neonatal intensive care unit (NICU)-associated sepsis. We used comparative genomic analyses of S. capitis to provide new insights into commensal scalp isolates from varying skin states (healthy, dandruff lesional, and non-lesional), and to expand our current knowledge of the species populations (scalp isolates, n = 59; other skin isolates, n = 7; publicly available isolates, n = 120). A highly recombinogenic population structure was revealed, with genomes including the presence of a range of previously described staphylococcal virulence factors, cell wall-associated proteins, and two-component systems. Genomic differences between the two described S. capitis subspecies were explored, which revealed the determinants associated exclusively with each subspecies. The subspecies ureolyticus was distinguished from subspecies capitis based on the differences in antimicrobial resistance genes, β-lactam resistance genes, and β-class phenol soluble modulins and gene clusters linked to biofilm formation and survival on skin. This study will aid further research into the classification of S. capitis and virulence-linked phylogroups to monitor the spread and evolution of S. capitis.
Collapse
|
11
|
Vlaeminck J, Lin Q, Xavier BB, De Backer S, Berkell M, De Greve H, Hernalsteens JP, Kumar-Singh S, Goossens H, Malhotra-Kumar S. The dynamic transcriptome during maturation of biofilms formed by methicillin-resistant Staphylococcus aureus. Front Microbiol 2022; 13:882346. [PMID: 35966712 PMCID: PMC9366926 DOI: 10.3389/fmicb.2022.882346] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 07/04/2022] [Indexed: 01/21/2023] Open
Abstract
BackgroundMethicillin-resistant Staphylococcus aureus (MRSA), a leading cause of chronic infections, forms prolific biofilms which afford an escape route from antibiotic treatment and host immunity. However, MRSA clones are genetically diverse, and mechanisms underlying biofilm formation remain under-studied. Such studies form the basis for developing targeted therapeutics. Here, we studied the temporal changes in the biofilm transcriptome of three pandemic MRSA clones: USA300, HEMRSA-15, and ST239.MethodsBiofilm formation was assessed using a static model with one representative strain per clone. Total RNA was extracted from biofilm and planktonic cultures after 24, 48, and 72 h of growth, followed by rRNA depletion and sequencing (Illumina Inc., San Diego, CA, United States, NextSeq500, v2, 1 × 75 bp). Differentially expressed gene (DEG) analysis between phenotypes and among early (24 h), intermediate (48 h), and late (72 h) stages of biofilms was performed together with in silico co-expression network construction and compared between clones. To understand the influence of SCCmec and ACME on biofilm formation, isogenic mutants containing deletions of the entire elements or of single genes therein were constructed in USA300.ResultsGenes involved in primarily core genome-encoded KEGG pathways (transporters and others) were upregulated in 24-h biofilm culture compared to 24-h planktonic culture. However, the number of affected pathways in the ST239 24 h biofilm (n = 11) was remarkably lower than that in USA300/EMRSA-15 biofilms (USA300: n = 27, HEMRSA-15: n = 58). The clfA gene, which encodes clumping factor A, was the single common DEG identified across the three clones in 24-h biofilm culture (2.2- to 2.66-fold). In intermediate (48 h) and late (72 h) stages of biofilms, decreased expression of central metabolic and fermentative pathways (glycolysis/gluconeogenesis, fatty acid biosynthesis), indicating a shift to anaerobic conditions, was already evident in USA300 and HEMRSA-15 in 48-h biofilm cultures; ST239 showed a similar profile at 72 h. Last, SCCmec+ACME deletion and opp3D disruption negatively affected USA300 biofilm formation.ConclusionOur data show striking differences in gene expression during biofilm formation by three of the most important pandemic MRSA clones, USA300, HEMRSA-15, and ST239. The clfA gene was the only significantly upregulated gene across all three strains in 24-h biofilm cultures and exemplifies an important target to disrupt early biofilms. Furthermore, our data indicate a critical role for arginine catabolism pathways in early biofilm formation.
Collapse
Affiliation(s)
- Jelle Vlaeminck
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Qiang Lin
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Basil Britto Xavier
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Sarah De Backer
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Matilda Berkell
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
- Molecular Pathology Group, Laboratory of Cell Biology & Histology, University of Antwerp, Antwerp, Belgium
| | - Henri De Greve
- VIB-VUB Center for Structural Biology, Vrije Universiteit Brussel, Brussels, Belgium
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium
| | | | - Samir Kumar-Singh
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
- Molecular Pathology Group, Laboratory of Cell Biology & Histology, University of Antwerp, Antwerp, Belgium
| | - Herman Goossens
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Surbhi Malhotra-Kumar
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
- *Correspondence: Surbhi Malhotra-Kumar,
| |
Collapse
|
12
|
Zhao N, Xu J, Jiao L, Liu M, Zhang T, Li J, Wei X, Fan M. Acid adaptive response of Alicyclobacillus acidoterrestris: A strategy to survive lethal heat and acid stresses. Food Res Int 2022; 157:111364. [DOI: 10.1016/j.foodres.2022.111364] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/05/2022] [Accepted: 05/10/2022] [Indexed: 11/26/2022]
|
13
|
Costa FG, Horswill AR. Overcoming pH defenses on the skin to establish infections. PLoS Pathog 2022; 18:e1010512. [PMID: 35617212 PMCID: PMC9135183 DOI: 10.1371/journal.ppat.1010512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Skin health is influenced by the composition and integrity of the skin barrier. The healthy skin surface is an acidic, hypertonic, proteinaceous, and lipid-rich environment that microorganisms must adapt to for survival, and disruption of this environment can result in dysbiosis and increase risk for infectious diseases. This work provides a brief overview of skin barrier function and skin surface composition from the perspective of how the most common skin pathogen, Staphylococcus aureus, combats acid stress. Advancements in replicating this environment in the laboratory setting for the study of S. aureus pathogenesis on the skin, as well as future directions in this field, are also discussed.
Collapse
Affiliation(s)
- Flavia G. Costa
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Alexander R. Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- Department of Veterans Affairs, Eastern Colorado Healthcare System, Aurora, Colorado, United States of America
- * E-mail:
| |
Collapse
|
14
|
Chu LC, Arede P, Li W, Urdaneta EC, Ivanova I, McKellar SW, Wills JC, Fröhlich T, von Kriegsheim A, Beckmann BM, Granneman S. The RNA-bound proteome of MRSA reveals post-transcriptional roles for helix-turn-helix DNA-binding and Rossmann-fold proteins. Nat Commun 2022; 13:2883. [PMID: 35610211 PMCID: PMC9130240 DOI: 10.1038/s41467-022-30553-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 05/06/2022] [Indexed: 01/21/2023] Open
Abstract
RNA-binding proteins play key roles in controlling gene expression in many organisms, but relatively few have been identified and characterised in detail in Gram-positive bacteria. Here, we globally analyse RNA-binding proteins in methicillin-resistant Staphylococcus aureus (MRSA) using two complementary biochemical approaches. We identify hundreds of putative RNA-binding proteins, many containing unconventional RNA-binding domains such as Rossmann-fold domains. Remarkably, more than half of the proteins containing helix-turn-helix (HTH) domains, which are frequently found in prokaryotic transcription factors, bind RNA in vivo. In particular, the CcpA transcription factor, a master regulator of carbon metabolism, uses its HTH domain to bind hundreds of RNAs near intrinsic transcription terminators in vivo. We propose that CcpA, besides acting as a transcription factor, post-transcriptionally regulates the stability of many RNAs.
Collapse
Affiliation(s)
- Liang-Cui Chu
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Pedro Arede
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Wei Li
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Erika C Urdaneta
- IRI Life Sciences, Humboldt University Berlin, 10115, Berlin, Germany
| | - Ivayla Ivanova
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Stuart W McKellar
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Jimi C Wills
- Cancer Research UK Edinburgh Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, EH4 2XR, UK
| | - Theresa Fröhlich
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Alexander von Kriegsheim
- Cancer Research UK Edinburgh Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, EH4 2XR, UK
| | | | - Sander Granneman
- Centre for Synthetic and Systems Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK.
| |
Collapse
|
15
|
Fellner M. Newly discovered Staphylococcus aureus serine hydrolase probe and drug targets. ADMET AND DMPK 2022; 10:107-114. [PMID: 35350120 PMCID: PMC8957240 DOI: 10.5599/admet.1137] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 10/25/2021] [Indexed: 11/18/2022] Open
Abstract
There is an urgent need for new diagnosis and treatment options for the bacterial pathogen Staphylococcus aureus. This review will summarize data on ten recently discovered biofilm-associated serine hydrolases called fluorophosphonate-binding hydrolases (FphA-J). Based on the summarized findings, many of these proteins represent intriguing new targets for probe and drug development.
Collapse
Affiliation(s)
- Matthias Fellner
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand. ; Tel.: +64 34797897
| |
Collapse
|
16
|
Metal sequestration by S100 proteins in chemically diverse environments. Trends Microbiol 2022; 30:654-664. [DOI: 10.1016/j.tim.2021.12.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 12/22/2022]
|
17
|
Paudel A, Panthee S, Hamamoto H, Grunert T, Sekimizu K. YjbH regulates virulence genes expression and oxidative stress resistance in Staphylococcus aureus. Virulence 2021; 12:470-480. [PMID: 33487122 PMCID: PMC7849776 DOI: 10.1080/21505594.2021.1875683] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 01/04/2021] [Accepted: 01/10/2021] [Indexed: 12/14/2022] Open
Abstract
We previously reported that disruption of the yjbI gene reduced virulence of Staphylococcus aureus. In this study, we found virulence in both silkworms and mice was restored by introducing the yjbH gene but not the yjbI gene to both yjbI and yjbH genes-disrupted mutants, suggesting that yjbH, the gene downstream to the yjbI gene in a two-gene operon-yjbIH, is responsible for this phenomenon. We further observed a decrease in various surface-associated proteins and changes in cell envelope glycostructures in the mutants. RNA-seq analysis revealed that disruption of the yjbI and the yjbH genes resulted in differential expression of a broad range of genes, notably, significant downregulation of genes involved in virulence and oxidative stress. Administration of N-acetyl-L-cysteine, a free-radical scavenger, restored the virulence in both the mutants. Our findings suggested that YjbH plays a role in staphylococcal pathogenicity by regulating virulence gene expression, affecting the bacterial surface structure, and conferring resistance to oxidative stress in a host.
Collapse
Affiliation(s)
- Atmika Paudel
- Teikyo University Institute of Medical Mycology, Hachioji, Tokyo, Japan
- Division of Infection and Immunity, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Suresh Panthee
- Teikyo University Institute of Medical Mycology, Hachioji, Tokyo, Japan
| | - Hiroshi Hamamoto
- Teikyo University Institute of Medical Mycology, Hachioji, Tokyo, Japan
| | - Tom Grunert
- Functional Microbiology, Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Kazuhisa Sekimizu
- Teikyo University Institute of Medical Mycology, Hachioji, Tokyo, Japan
| |
Collapse
|
18
|
Anil A, Apte S, Joseph J, Parthasarathy A, Madhavan S, Banerjee A. Pyruvate Oxidase as a Key Determinant of Pneumococcal Viability during Transcytosis across Brain Endothelium. J Bacteriol 2021; 203:e0043921. [PMID: 34606370 PMCID: PMC8604078 DOI: 10.1128/jb.00439-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 09/23/2021] [Indexed: 01/23/2023] Open
Abstract
Streptococcus pneumoniae invades a myriad of host tissues following efficient breaching of cellular barriers. However, strategies adopted by pneumococcus for evasion of host intracellular defenses governing successful transcytosis across host cellular barriers remain elusive. In this study, using brain endothelium as a model host barrier, we observed that pneumococcus containing endocytic vacuoles (PCVs), formed following S. pneumoniae internalization into brain microvascular endothelial cells (BMECs), undergo early maturation and acidification, with a major subset acquiring lysosome-like characteristics. Exploration of measures that would preserve pneumococcal viability in the lethal acidic pH of these lysosome-like vacuoles revealed a critical role of the two-component system response regulator, CiaR, which was previously implicated in induction of acid tolerance response. Pyruvate oxidase (SpxB), a key sugar-metabolizing enzyme that catalyzes oxidative decarboxylation of pyruvate to acetyl phosphate, was found to contribute to acid stress tolerance, presumably via acetyl phosphate-mediated phosphorylation and activation of CiaR, independent of its cognate kinase CiaH. Hydrogen peroxide, the by-product of an SpxB-catalyzed reaction, was also found to improve pneumococcal intracellular survival by oxidative inactivation of lysosomal cysteine cathepsins, thus compromising the degradative capacity of the host lysosomes. As expected, a ΔspxB mutant was found to be significantly attenuated in its ability to survive inside the BMEC endocytic vacuoles, reflecting its reduced transcytosis ability. Collectively, our studies establish SpxB as an important virulence determinant facilitating pneumococcal survival inside host cells, ensuring successful trafficking across host cellular barriers. IMPORTANCE Host cellular barriers have innate immune defenses to restrict microbial passage into sterile compartments. Here, by focusing on the blood-brain barrier endothelium, we investigated mechanisms that enable Streptococcus pneumoniae to traverse through host barriers. Pyruvate oxidase, a pneumococcal sugar-metabolizing enzyme, was found to play a crucial role in this via generation of acetyl phosphate and hydrogen peroxide. A two-pronged approach consisting of acetyl phosphate-mediated activation of acid tolerance response and hydrogen peroxide-mediated inactivation of lysosomal enzymes enabled pneumococci to maintain viability inside the degradative vacuoles of the brain endothelium for successful transcytosis across the barrier. Thus, pyruvate oxidase is a key virulence determinant and can potentially serve as a viable candidate for therapeutic interventions for better management of invasive pneumococcal diseases.
Collapse
Affiliation(s)
- Anjali Anil
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Shruti Apte
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Jincy Joseph
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Akhila Parthasarathy
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Shilpa Madhavan
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Anirban Banerjee
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| |
Collapse
|
19
|
A Combination of Genomics, Transcriptomics, and Genetics Provides Insights into the Mineral Weathering Phenotype of Pseudomonas azotoformans F77. Appl Environ Microbiol 2021; 87:e0155221. [PMID: 34586903 DOI: 10.1128/aem.01552-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Silicate mineral weathering (dissolution) plays important roles in soil formation and global biogeochemical cycling. In this study, a combination of genomics, transcriptomics, and genetics was used to identify the molecular basis of mineral weathering activity and acid tolerance in Pseudomonas azotoformans F77. Biotite was chosen as a silicate mineral to investigate mineral weathering. The genome of strain F77 was sequenced, and the genes significantly upregulated when grown in the presence of biotite included mineral weathering-related genes associated with gluconic acid metabolism, flagellar assembly, and pilus biosynthesis and acid tolerance-related genes associated with neutralizing component production, reducing power, and proton efflux. Then, the biotite-weathering behaviors of strain F77 and its mutants that were created by deleting the tkt, tal, gntP, potF, nuoF, and gdtO genes, which are involved in gluconic acid metabolism and acid tolerance, respectively, were determined. The Fe and Al concentrations in the strain F77-inoculated medium increased 2.2- to 13.7-fold compared to the controls. The cell numbers of strain F77 increased over time, while the pH values in the medium ranged from 3.75 to 3.90 between 20 and 36 h of incubation. The release of Al and Fe was significantly reduced in the mutants F77Δtal, F77ΔgntP, F77ΔpotF, and F77ΔnuoF. Bacterial growth was significantly reduced in the presence of biotite in the mutants F77ΔpotF and F77ΔnuoF. Our results demonstrated the acid tolerance of strain F77 and suggested that multiple genes and metabolic pathways in strain F77 are involved in biotite weathering and acid tolerance during the mineral weathering process. IMPORTANCE Acid production and tolerance play important roles in effective and persistent mineral weathering in bacteria, although the molecular mechanisms governing acid production and acid tolerance in bacteria have not been fully elucidated. In this study, the molecular mechanisms underlying biotite (as a silicate mineral) weathering (dissolution) and acid tolerance of P. azotoformans F77 were characterized using genomics, transcriptomics, and genetics analyses. Our results showed that the genes and metabolic pathways for gluconic acid metabolism, flagellar assembly, and pilus biosynthesis may play important roles in mineral weathering by strain F77. Notably, the genes associated with neutralizing component production, reducing power, and proton efflux may be related to acid tolerance in strain F77. The expression of these acid production- and acid tolerance-related genes was observed to be increased by biotite in strain F77. Our findings may help to elucidate the molecular mechanisms governing mineral weathering and, especially, acid tolerance in mineral-weathering bacteria.
Collapse
|
20
|
Raineri EJM, Altulea D, van Dijl JM. Staphylococcal trafficking and infection - from 'nose to gut' and back. FEMS Microbiol Rev 2021; 46:6321165. [PMID: 34259843 PMCID: PMC8767451 DOI: 10.1093/femsre/fuab041] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 07/11/2021] [Indexed: 12/12/2022] Open
Abstract
Staphylococcus aureus is an opportunistic human pathogen, which is a leading cause of infections worldwide. The challenge in treating S. aureus infection is linked to the development of multidrug-resistant strains and the mechanisms employed by this pathogen to evade the human immune defenses. In addition, S. aureus can hide asymptomatically in particular ‘protective’ niches of the human body for prolonged periods of time. In the present review, we highlight recently gained insights in the role of the human gut as an endogenous S. aureus reservoir next to the nasopharynx and oral cavity. In addition, we address the contribution of these ecological niches to staphylococcal transmission, including the roles of particular triggers as modulators of the bacterial dissemination. In this context, we present recent advances concerning the interactions between S. aureus and immune cells to understand their possible roles as vehicles of dissemination from the gut to other body sites. Lastly, we discuss the factors that contribute to the switch from colonization to infection. Altogether, we conclude that an important key to uncovering the pathogenesis of S. aureus infection lies hidden in the endogenous staphylococcal reservoirs, the trafficking of this bacterium through the human body and the subsequent immune responses.
Collapse
Affiliation(s)
- Elisa J M Raineri
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Dania Altulea
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jan Maarten van Dijl
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| |
Collapse
|
21
|
Nasser A, Dallal MMS, Jahanbakhshi S, Azimi T, Nikouei L. Staphylococcus aureus: biofilm formation and strategies against it. Curr Pharm Biotechnol 2021; 23:664-678. [PMID: 34238148 DOI: 10.2174/1389201022666210708171123] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 05/09/2021] [Accepted: 05/31/2021] [Indexed: 11/22/2022]
Abstract
The formation of Staphylococcus aureus biofilm causes significant infections in the human body. Biofilm forms through the aggregation of bacterial species and brings about many complications. It mediates drug resistance and persistence and facilitates the recurrence of infection at the end of antimicrobial therapy. Biofilm formation goes through a series of steps to complete, and any interference in these steps can disrupt its formation. Such interference may occur at any stage of biofilm production, including attachment, monolayer formation, and accumulation. Interfering agents can act as quorum sensing inhibitors and interfere in the functionality of quorum sensing receptors, attachment inhibitors and affect the cell hydrophobicity. Among these inhibiting strategies, attachment inhibitors could serve as the best agents against biofilm formation. If pathogens abort the attachment, the following stages of biofilm formation, e.g., accumulation and dispersion, will fail to materialize. Inhibition at this stage leads to suppression of virulence factors and invasion. One of the best-known inhibitors is a chelator that collects metal, Fe+, Zn+, and magnesium critical for biofilm formation. These influential factors in the binding and formation of biofilm are investigated, and the coping strategy is discussed. This review examines the stages of biofilm formation and determines what factors interfere in the continuity of these steps. Finally, the inhibition strategies are investigated, reviewed, and discussed. Keywords: Biofilm, Staphylococcus, Biofilm inhibitor, Dispersion, Antibiofilm agent, EPS, PIA.
Collapse
Affiliation(s)
- Ahmad Nasser
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Shiva Jahanbakhshi
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Taher Azimi
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Leila Nikouei
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
22
|
Zhang Y, Deng Y, Feng J, Guo Z, Chen H, Wang B, Hu J, Lin Z, Su Y. Functional characterization of VscCD, an important component of the type Ⅲ secretion system of Vibrio harveyi. Microb Pathog 2021; 157:104965. [PMID: 34015493 DOI: 10.1016/j.micpath.2021.104965] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/23/2021] [Accepted: 05/11/2021] [Indexed: 11/19/2022]
Abstract
Vibrio harveyi is a Gram-negative bacterium that occurs widely in the ocean and a kind of pathogenic bacteria associated with vibriosis in grouper. We investigated whether the VscCD protein of the type Ⅲ secretion system (T3SS) was important for pathogenicity of V. harveyi. Mutations to the vscC and vscD genes (ΔvscCD) and complementation of the ΔvscCD mutant (C-ΔvscCD) were created. Moreover, the biological characteristics of the wild-type (WT) and mutant strains of V. harveyi 345 were compared. The results showed that deletion of the vscCD genes had no effect on bacterial growth, swimming/swarming ability, secretion of extracellular protease, or biofilm formation. However, as compared with the V. harveyi 345: pMMB207 (WT+) and complementary (C-ΔvscCD) strains, the ΔvscCD: pMMB207 (ΔvscCD+) mutant displayed decreased resistance to acid stress, H2O2, and antibiotics. In addition, infection of the pearl gentian grouper (♀Epinephelus fuscoguttatus × ♂Epinephelus lanceolatu) showed that as compared with the WT+ and C-ΔvscCD strains, the ΔvscCD+ strain significantly reduced cumulative mortality of the host. The colonization ability of the ΔvscCD+ mutant in the spleen and liver tissues of the pearl gentian grouper was significantly lower than that of the WT+ and C-ΔvscCD strains. In the early stage of infection with the ΔvscCD+ strain, the expression levels of IL-1β, IL-16, TLR3, TNF-α, MHC-Iα, and CD8α were up-regulated to varying degrees. As compared with the WT+ and C-ΔvscCD strains, luxR expression was significantly up-regulated in the ΔvscCD+ strain, while the expression of vcrH and vp1668 was significantly down-regulated. As an important component of the T3SS, VscCD seemed to play a significant role in the pathogenesis of V. harveyi.
Collapse
Affiliation(s)
- Yaqiu Zhang
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Yiqin Deng
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China.
| | - Juan Feng
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China
| | - Zhixun Guo
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China
| | - Haoxiang Chen
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Baotun Wang
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Jianmei Hu
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Ziyang Lin
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China
| | - Youlu Su
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; Innovative Institute of Animal Healthy Breeding, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China.
| |
Collapse
|
23
|
Pidwill GR, Gibson JF, Cole J, Renshaw SA, Foster SJ. The Role of Macrophages in Staphylococcus aureus Infection. Front Immunol 2021; 11:620339. [PMID: 33542723 PMCID: PMC7850989 DOI: 10.3389/fimmu.2020.620339] [Citation(s) in RCA: 144] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 12/02/2020] [Indexed: 12/23/2022] Open
Abstract
Staphylococcus aureus is a member of the human commensal microflora that exists, apparently benignly, at multiple sites on the host. However, as an opportunist pathogen it can also cause a range of serious diseases. This requires an ability to circumvent the innate immune system to establish an infection. Professional phagocytes, primarily macrophages and neutrophils, are key innate immune cells which interact with S. aureus, acting as gatekeepers to contain and resolve infection. Recent studies have highlighted the important roles of macrophages during S. aureus infections, using a wide array of killing mechanisms. In defense, S. aureus has evolved multiple strategies to survive within, manipulate and escape from macrophages, allowing them to not only subvert but also exploit this key element of our immune system. Macrophage-S. aureus interactions are multifaceted and have direct roles in infection outcome. In depth understanding of these host-pathogen interactions may be useful for future therapeutic developments. This review examines macrophage interactions with S. aureus throughout all stages of infection, with special emphasis on mechanisms that determine infection outcome.
Collapse
Affiliation(s)
- Grace R. Pidwill
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
| | - Josie F. Gibson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
- The Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Joby Cole
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom
| | - Stephen A. Renshaw
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
- The Bateson Centre, University of Sheffield, Sheffield, United Kingdom
- Department of Infection, Immunity and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom
| | - Simon J. Foster
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
- Florey Institute, University of Sheffield, Sheffield, United Kingdom
| |
Collapse
|
24
|
Spinelli E, Requena T, Caruso M, Parisi A, Capozzi L, Difato L, Normanno G. Fate of Methicillin-resistant Staphylococcus aureus (MRSA) under simulated acidic conditions of the human stomach. Food Sci Nutr 2020; 8:4739-4745. [PMID: 32994935 PMCID: PMC7500784 DOI: 10.1002/fsn3.1698] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 05/09/2020] [Accepted: 05/13/2020] [Indexed: 01/09/2023] Open
Abstract
A known amount (107 cfu/ml) of animal origin Methicillin-resistant Staphylococcus aureus (MRSA) ST398/t011/V and of human origin MRSA ST1/t127/IVa strains were individually inoculated into ricotta cheese and hamburger samples. The pH of each food matrix was gradually decreased from 6.0 down to 2.0 during a period of about 2 hr, under conditions simulating the mechanical digestion of the human stomach. Afterward, the MRSA strains were recovered by using a MRSA-specific plating medium. Although both strains showed a certain acidic resistance, they showed different responses at low pH values during the experiment: ST398 survived unharmed during the course of the experiments to the last stage at pH 2 where counts of 6.4 cfu/g for the hamburger and 7.5 log cfu/g for ricotta cheese assays were obtained. In contrast, the ST1 population was no longer detectable at pH 3 in the hamburger and at pH 2 in the ricotta cheese assays. To the best of our knowledge, this is the first study that investigates the ability of MRSA to overcome the acidic conditions of the human stomach and that adds new evidence that might contribute to expand the scientific knowledge on the significance of MRSA in the food safety debate.
Collapse
Affiliation(s)
- Elisa Spinelli
- Department of Science of Agriculture, Food and the Environment (SAFE) University of Foggia Foggia Italy
| | - Teresa Requena
- Research Institute of Food Science CIAL (CSIC-UAM) Madrid Spain
| | - Marta Caruso
- Experimental Zooprophylactic Institute of Apulia and Basilicata Matera Italy
| | - Antonio Parisi
- Experimental Zooprophylactic Institute of Apulia and Basilicata Putignano Italy
| | - Loredana Capozzi
- Experimental Zooprophylactic Institute of Apulia and Basilicata Putignano Italy
| | - Laura Difato
- Experimental Zooprophylactic Institute of Apulia and Basilicata Matera Italy
| | - Giovanni Normanno
- Department of Science of Agriculture, Food and the Environment (SAFE) University of Foggia Foggia Italy
| |
Collapse
|
25
|
Rosen T, Nolan EM. Metal Sequestration and Antimicrobial Activity of Human Calprotectin Are pH-Dependent. Biochemistry 2020; 59:2468-2478. [PMID: 32491853 DOI: 10.1021/acs.biochem.0c00359] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Human calprotectin (CP, S100A8/S100A9 oligomer) is an abundant innate immune protein that sequesters transition metal ions in the extracellular space to limit nutrient availability and the growth of invading microbial pathogens. Our current understanding of the metal-sequestering ability of CP is based on biochemical and functional studies performed at neutral or near-neutral pH. Nevertheless, CP can be present throughout the human body and is expressed at infection and inflammation sites that tend to be acidic. Here, we evaluate the metal binding and antimicrobial properties of CP in the pH range of 5.0-7.0. We show that Ca(II)-induced tetramerization, an important process for the extracellular functions of CP, is perturbed by acidic conditions. Moreover, a low pH impairs the antimicrobial activity of CP against some bacterial pathogens, including Staphylococcus aureus and Salmonella enterica serovar Typhimurium. At a mildly acidic pH, CP loses the ability to deplete Mn from microbial growth medium, indicating that Mn(II) sequestration is attenuated under acidic conditions. Evaluation of the Mn(II) binding properties of CP at pH 5.0-7.0 indicates that mildly acidic conditions decrease the Mn(II) binding affinity of the His6 site. Lastly, CP is less effective at preventing capture of Mn(II) by the bacterial solute-binding proteins MntC and PsaA at low pH. These results indicate that acidic conditions compromise the ability of CP to sequester Mn(II) and starve microbial pathogens of this nutrient. This work highlights the importance of considering the local pH of biological sites when describing the interplay between CP and microbes in host-pathogen interactions.
Collapse
Affiliation(s)
- Tomer Rosen
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Elizabeth M Nolan
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| |
Collapse
|
26
|
Zhou C, Fey PD. The acid response network of Staphylococcus aureus. Curr Opin Microbiol 2020; 55:67-73. [PMID: 32361405 PMCID: PMC7311314 DOI: 10.1016/j.mib.2020.03.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 03/17/2020] [Accepted: 03/18/2020] [Indexed: 12/12/2022]
Abstract
Staphylococcus aureus colonizes or causes infection in a multitude of niches within a mammalian host. Many of these niches are acidic, yet specific pH resistance mechanisms that facilitate survival have not been thoroughly investigated. This review discusses recent studies documenting known acid resistance mechanisms in S. aureus and other staphylococcal species. However, studies that clearly define the regulation of the acid resistance regulon and potential interactions with weak organic acids in specific niches of the host including the skin and gut are yet to be defined.
Collapse
Affiliation(s)
- Chunyi Zhou
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, United States
| | - Paul D Fey
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, United States.
| |
Collapse
|
27
|
Ebani VV, Bertelloni F, Najar B, Nardoni S, Pistelli L, Mancianti F. Antimicrobial Activity of Essential Oils against Staphylococcus and Malassezia Strains Isolated from Canine Dermatitis. Microorganisms 2020; 8:microorganisms8020252. [PMID: 32069976 PMCID: PMC7074795 DOI: 10.3390/microorganisms8020252] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 02/04/2020] [Accepted: 02/12/2020] [Indexed: 02/06/2023] Open
Abstract
Staphylococcus spp. bacteria are the most frequently involved agents in canine cutaneous infections. Treatment of these infections is based on antibiotic therapy, that often is not effective because of the antibiotic-resistance of the bacterial strains. Cutaneous staphylococcal infections are often complicated by Malassezia yeasts, that may be resistant to the conventional antifungal drugs. The present investigation was aimed to evaluate the in vitro antimicrobial activity of some essential oils (EOs) in view of a potential cutaneous application. In detail, EOs obtained from lemon verbena (Aloysia triphylla L'Hèr. Britton), cinnamon (Cinnamomum zeylanicum J. Presl), myrrh (Commiphora myrrha (Nees) Engl. var. molmol), lemongrass (Cymbopogon citratus (DC.) Stapf), litsea (Litsea cubeba (Lour.) Pers.), lemon balm (Melissa officinalis L.), oregano (Origanum vulgare L.), savory (Satureja montana L.), and thyme (Thymus vulgaris L.) were assayed against Staphylococcus spp. and Malassezia pachydermatis strains previously isolated from dogs with dermatitis. All EOs were tested by agar disk diffusion and minimum inhibitory concentration methods to verify the antistaphylococcal activity, and by a microdilution method to evaluate the activity against M. pachydermatis. O. vulgare, T. vulgaris, and S. montana showed the best antibacterial activity against all the selected strains, with MICs ranging from 0.29 to 0.58 mg/mL, from 0.58 to 1.16 mg/mL, and from 0.56 to 1.12 mg/mL, respectively, whereas A. triphylla (1.03 mg/mL) and S. montana (1.8 mg/mL) were the most active against M. pachydermatis. After a proper in vivo evaluation, O. vulgare, T. vulgaris, and S. montana EOs could be a promising treatment to combat canine cutaneous mixed infections.
Collapse
Affiliation(s)
- Valentina Virginia Ebani
- Department of Veterinary Science, University of Pisa, Viale delle Piagge 2, 56124 Pisa, Italy; (F.B.); (S.N.); (F.M.)
- Centro Interdipartimentale di Ricerca “Nutraceutica e Alimentazione per la Salute”, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy;
- Correspondence: ; Tel.: +39-05-0221-6968
| | - Fabrizio Bertelloni
- Department of Veterinary Science, University of Pisa, Viale delle Piagge 2, 56124 Pisa, Italy; (F.B.); (S.N.); (F.M.)
| | - Basma Najar
- Department of Pharmacy, University of Pisa, via Bonanno 6, 56126 Pisa, Italy;
| | - Simona Nardoni
- Department of Veterinary Science, University of Pisa, Viale delle Piagge 2, 56124 Pisa, Italy; (F.B.); (S.N.); (F.M.)
| | - Luisa Pistelli
- Centro Interdipartimentale di Ricerca “Nutraceutica e Alimentazione per la Salute”, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy;
- Department of Pharmacy, University of Pisa, via Bonanno 6, 56126 Pisa, Italy;
| | - Francesca Mancianti
- Department of Veterinary Science, University of Pisa, Viale delle Piagge 2, 56124 Pisa, Italy; (F.B.); (S.N.); (F.M.)
- Centro Interdipartimentale di Ricerca “Nutraceutica e Alimentazione per la Salute”, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy;
| |
Collapse
|
28
|
Narenji H, Teymournejad O, Rezaee MA, Taghizadeh S, Mehramuz B, Aghazadeh M, Asgharzadeh M, Madhi M, Gholizadeh P, Ganbarov K, Yousefi M, Pakravan A, Dal T, Ahmadi R, Samadi Kafil H. Antisense peptide nucleic acids againstftsZ andefaA genes inhibit growth and biofilm formation of Enterococcusfaecalis. Microb Pathog 2019; 139:103907. [PMID: 31811888 DOI: 10.1016/j.micpath.2019.103907] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 11/23/2019] [Accepted: 12/02/2019] [Indexed: 12/25/2022]
Abstract
Enterococcus faecalis is one of the important causes of nosocomial infections. Nowadays, increasing prevalence of antibiotic-resistant bacteria and slow progress in recognizing new antimicrobial agents has limited the efficiency of conventional antibiotics, which cause to find novel strategies to overcome bacteria. Therefore, in this study, we aimed to assess the role of efaA gene in the biofilm formation and the role of ftsZ gene in the controlling of bacterial growth by the anti-sense PNAs(Peptide Nucleic Acid).E. faecalis ATCC® 29212™was used for the study of PNAs designed to targeting the start codon section of the ftsZ andefaA genes. PNA attachment to RNA was confirmed by blotting. Electroporation technique was used for the intracellular transfer of anti-ftsZ PNAs. The spot-plating method was used to the assessment of alteration in bacterial growth. Biofilm formation assay and real-time PCR were used for detection of biofilm inhibitory effect of cell penetrating peptide (CPP) conjugated to anti-efaA PNAs.ByftsZ PNAs treatment, no growth was seen from the strain in agar by a spot plating method and the inhibition zone of anti-ftsZ PNAs was not seen. PNAs against the efaA gene decreased by 95% the expression of the efaA gene and biofilm formation. In addition, the(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) MTT assay showed no toxicity on MCF7 cells for both of anti-ftsZand anti-efaA PNAs.This study used new genetic and molecular tools to inhibit pathogenicity and infection by E. faecalis. In this study, we suggested that efaA gene plays a critical role in the biofilm formation and anti-efaA PNAs could decrease the formation of biofilm, as well as, anti-ftsZ PNAs could eliminate bacterial growth.
Collapse
Affiliation(s)
- Hanar Narenji
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Omid Teymournejad
- Department of Veterinary Biosciences, Ohio State University, Columbus, OH, 43210, United States
| | | | - Sepehr Taghizadeh
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Bahareh Mehramuz
- Immunology Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Aghazadeh
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Asgharzadeh
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Masoumeh Madhi
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Pourya Gholizadeh
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Mehdi Yousefi
- Immunology Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Asrin Pakravan
- Department of Chemistry, Faculty of Basic Sciences, Azarbaijan Shahid Madani University, Tabriz, Iran
| | - Tuba Dal
- Department of Clinical Microbiology, Faculty of Medicine, Ankara Yildirim Beyazit University, Ankara, Turkey
| | - Raman Ahmadi
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hossein Samadi Kafil
- Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
| |
Collapse
|
29
|
Ali SA, Singh P, Tomar SK, Mohanty AK, Behare P. Proteomics fingerprints of systemic mechanisms of adaptation to bile in Lactobacillus fermentum. J Proteomics 2019; 213:103600. [PMID: 31805390 DOI: 10.1016/j.jprot.2019.103600] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 11/17/2019] [Accepted: 11/28/2019] [Indexed: 12/17/2022]
Abstract
Lactobacillus fermentum is a natural resident of the human GIT and is used as a probiotic. A unique property of L. fermentum is its ability to tolerate, colonize, and survive in the harsh conditions of bile, which facilitates transient colonization of the host colon. In the current study, we investigated the key mechanisms of action involved in bacterial survival in the presence of bile, using high-resolution mass spectrometry. A total of 1071 proteins were identified, among which 378 were up-regulated and 368 down-regulated by ≥2-fold (t-test, p < .05). Differentially regulated proteins comprised both intracellular and surface-exposed (i.e., membrane) proteins (p < .01, t-test for total proteome analysis; p < .05, t-test for membrane proteome analysis). These alterations strengthen the cell envelope and also mediate bile efflux by adjusting carbohydrate metabolic pathways and prevention of protein misfolding. These processes are mainly involved in the active removal of bile salts or amelioration of its adverse effects on cells. Further investigation of mRNA transcript expression levels of selected proteins by quantitative reverse transcriptase-PCR verified the proteomic data. Together, our proteomics findings reveal the roles of post-stress recovery proteins and highlight the interacting pathways responsible for bacterial cell tolerance to bile stress. BIOLOGICAL SIGNIFICANCE: Our intestinal tract is a nutrient-rich milieu crowded with up to 100 trillion (1014) of microbes. The fact that we are born germ-free describes that these microbes must colonize our intestinal tract from outside. However, their survival is also complicated because of hazardous conditions in the gut due to the presence of bile acid and others, which exerts a deleterious effect on the beneficial microbial load. While there was limited information available describing the comprehensive mechanism of survival? Furthermore, the imbalance of these micro floras leads to numerous disease conditions. It explains the need for enhanced understanding of host-microbe interactions in the colon. The present study majorly focuses on identifying "how microbes respond to environmental stressors" in this context, particularly bile acid response. This work addresses a fascinating cellular mechanism involved in the complex changes of bile induction in the microbial system; in this case, L. fermentum NCDC 605 a well established probiotic organism. In this article, we decipher the characteristic adaptation mechanism adjusted by probiotics in the harsh condition of 1.2% bile. The generated new knowledge will also improve the potential therapeutic efficacy of probiotics strains in clinical trials for patients of inflammatory bowel diseases (IBD) and related disorders.
Collapse
Affiliation(s)
- Syed Azmal Ali
- Proteomics and Cell Biology Lab, Animal Biotechnology Center, National Dairy Research Institute, Haryana, India.
| | - Parul Singh
- Proteomics and Cell Biology Lab, Animal Biotechnology Center, National Dairy Research Institute, Haryana, India
| | - Sudhir K Tomar
- National Collection of Dairy Cultures (NCDC) lab, Dairy Microbiology Division, National Dairy Research Institute, Haryana, India
| | - Ashok K Mohanty
- Proteomics and Cell Biology Lab, Animal Biotechnology Center, National Dairy Research Institute, Haryana, India
| | - Pradip Behare
- National Collection of Dairy Cultures (NCDC) lab, Dairy Microbiology Division, National Dairy Research Institute, Haryana, India.
| |
Collapse
|
30
|
Evaluation of adaptive response in E. coli O157:H7 to UV light and gallic acid based antimicrobial treatments. Food Control 2019. [DOI: 10.1016/j.foodcont.2019.106723] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
31
|
Efthimiou G, Tsiamis G, Typas MA, Pappas KM. Transcriptomic Adjustments of Staphylococcus aureus COL (MRSA) Forming Biofilms Under Acidic and Alkaline Conditions. Front Microbiol 2019; 10:2393. [PMID: 31681245 PMCID: PMC6813237 DOI: 10.3389/fmicb.2019.02393] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/02/2019] [Indexed: 01/13/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) strains are important human pathogens and a significant health hazard for hospitals and the food industry. They are resistant to β-lactam antibiotics including methicillin and extremely difficult to treat. In this study, we show that the Staphylococcus aureus COL (MRSA) strain, with a known complete genome, can easily survive and grow under acidic and alkaline conditions (pH5 and pH9, respectively), both planktonically and as a biofilm. A microarray-based analysis of both planktonic and biofilm cells was performed under acidic and alkaline conditions showing that several genes are up- or down-regulated under different environmental conditions and growth modes. These genes were coding for transcription regulators, ion transporters, cell wall biosynthetic enzymes, autolytic enzymes, adhesion proteins and antibiotic resistance factors, most of which are associated with biofilm formation. These results will facilitate a better understanding of the physiological adjustments occurring in biofilm-associated S. aureus COL cells growing in acidic or alkaline environments, which will enable the development of new efficient treatment or disinfection strategies.
Collapse
Affiliation(s)
- Georgios Efthimiou
- Department of Genetics and Biotechnology, Faculty of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - George Tsiamis
- Department of Environmental Engineering, University of Patras, Agrinio, Greece
| | - Milton A Typas
- Department of Genetics and Biotechnology, Faculty of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Katherine M Pappas
- Department of Genetics and Biotechnology, Faculty of Biology, National and Kapodistrian University of Athens, Athens, Greece
| |
Collapse
|
32
|
Cao L, Wang J, Sun L, Kong Z, Wu Q, Wang Z. Transcriptional analysis reveals the relativity of acid tolerance and antimicrobial peptide resistance of Salmonella. Microb Pathog 2019; 136:103701. [PMID: 31472260 DOI: 10.1016/j.micpath.2019.103701] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 08/27/2019] [Accepted: 08/28/2019] [Indexed: 01/20/2023]
Abstract
The objective of this study was to comprehensively identify the target genes induced by acid stimulation in Salmonella, and to clarify the relativity of acid tolerance and antimicrobial peptide resistance. A clinical S. Typhimurium strain, S6, was selected and performed a transcriptome analysis under the acid tolerance response. In total, we found 1461 genes to be differentially expressed, including 721 up-regulated and 740 down-regulated genes. Functional annotation revealed differentially expressed genes to be associated with regulation, metabolism, transport, virulence, and motility. Interestingly, KEGG pathway analysis demonstrated that the induced genes by acid were enriched in cationic antimicrobial peptide resistance, sulfur relay system, ABC transporters, and two-component system pathway. Therein, PhoQ belonging to the two-component system PhoP-PhoQ that promotes virulence by detecting the macrophage phagosome and controls the transcript levels of many genes associated with the resistance to AMPs; MarA, a multiple antibiotic resistance factor; SapA, one of the encoding gene of sapABCDF operon that confers resistance to small cationic peptides of Salmonella; YejB, one of the encoding gene of yejABEF operon that confers resistance to antimicrobial peptides and contributes to the virulence of Salmonella, were all induced by acid stimulation, and could potentially explain that there is a correlation between acid tolerance and AMPs resistance, and finally affects the virulence of intracellular pathogenic bacteria.
Collapse
Affiliation(s)
- Li Cao
- Beijing Key Laboratory of Traditional Chinese Veterinary Medicine, Animal Science and Technology College, Beijing University of Agriculture, Beijing, 102206, China
| | - Jiawei Wang
- Beijing Key Laboratory of Traditional Chinese Veterinary Medicine, Animal Science and Technology College, Beijing University of Agriculture, Beijing, 102206, China
| | - Lu Sun
- Beijing Key Laboratory of Traditional Chinese Veterinary Medicine, Animal Science and Technology College, Beijing University of Agriculture, Beijing, 102206, China
| | - Zian Kong
- Beijing Key Laboratory of Traditional Chinese Veterinary Medicine, Animal Science and Technology College, Beijing University of Agriculture, Beijing, 102206, China
| | - Qingmin Wu
- Key Laboratory of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Zhen Wang
- Beijing Key Laboratory of Traditional Chinese Veterinary Medicine, Animal Science and Technology College, Beijing University of Agriculture, Beijing, 102206, China.
| |
Collapse
|
33
|
Bishai WR, Timmins GS. Potential for breath test diagnosis of urease positive pathogens in lung infections. J Breath Res 2019; 13:032002. [DOI: 10.1088/1752-7163/ab2225] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
34
|
Alreshidi MM, Dunstan RH, Macdonald MM, Smith ND, Gottfries J, Roberts TK. Amino acids and proteomic acclimation of Staphylococcus aureus when incubated in a defined minimal medium supplemented with 5% sodium chloride. Microbiologyopen 2019; 8:e00772. [PMID: 30739392 PMCID: PMC6562129 DOI: 10.1002/mbo3.772] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 10/31/2018] [Accepted: 10/31/2018] [Indexed: 11/06/2022] Open
Abstract
Staphylococcus aureus is a versatile bacterium that can adapt to survive and grow in a wide range of salt concentrations. This study investigated whether the cells could mount a response to survive a challenge of 5% NaCl in a minimal incubation medium that would not support cell replication. Cells were grown in liquid culture, washed and then incubated for 90 min at 37°C in a medium that contained only glycine and glucose as substrates in PBS plus trace elements. The control cells were compared with a treatment group which was incubated with an additional 5% NaCl. Significantly more glycine was taken up by the cells exposed to 5% NaCl compared with control cells, and both groups consumed 99% of the glucose supplied. The NaCl treated cells had significantly higher cytoplasmic levels of proline and glutamic acid as well as lower levels of alanine and methionine compared with the controls (p < 0.05). The levels of the two major cytoplasmic amino acids, aspartic acid and glycine, remained constant in control and treated cells. Proteomic analyses revealed that 10 proteins showed differential responses between the control and treatment groups. The reductions in proteins were primarily associated with processes of protein biosynthesis, pathogenicity, and cell adhesion. Since cell numbers remained constant during the incubation period in minimal medium, it was concluded that there was no cell division to support population growth. The results provided evidence that the cells in the minimal medium exposed to the NaCl treatment underwent in situ homeostatic changes to adjust to the new environmental conditions. It was proposed that this represented a phenotypic shift to form cells akin to small colony variants, with lower metabolic rates and lower levels of key proteins associated with pathogenicity.
Collapse
Affiliation(s)
- Mousa M. Alreshidi
- Department of Biology, College of ScienceUniversity of HailHailSaudi Arabia
| | - R. Hugh Dunstan
- Metabolic Research Group, Faculty of ScienceSchool of Environmental and Life SciencesCallaghanNew South WalesAustralia
| | - Margaret M. Macdonald
- Metabolic Research Group, Faculty of ScienceSchool of Environmental and Life SciencesCallaghanNew South WalesAustralia
| | - Nathan D. Smith
- Analytical and Biomolecular Research Facility (ABRF)University of NewcastleCallaghanNew South WalesAustralia
| | - Johan Gottfries
- Department of ChemistryGothenburg UniversityGothenburgSweden
| | - Tim K. Roberts
- Metabolic Research Group, Faculty of ScienceSchool of Environmental and Life SciencesCallaghanNew South WalesAustralia
| |
Collapse
|
35
|
Zeng X, Pan Q, Guo Y, Wu Z, Sun Y, Dang Y, Cao J, He J, Pan D. Potential mechanism of nitrite degradation by Lactobacillus fermentum RC4 based on proteomic analysis. J Proteomics 2019; 194:70-78. [DOI: 10.1016/j.jprot.2018.12.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 12/03/2018] [Accepted: 12/18/2018] [Indexed: 02/06/2023]
|
36
|
Mikheyeva IV, Thomas JM, Kolar SL, Corvaglia AR, Gaϊa N, Leo S, Francois P, Liu GY, Rawat M, Cheung AL. YpdA, a putative bacillithiol disulfide reductase, contributes to cellular redox homeostasis and virulence in Staphylococcus aureus. Mol Microbiol 2019; 111:1039-1056. [PMID: 30636083 DOI: 10.1111/mmi.14207] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/27/2018] [Indexed: 11/28/2022]
Abstract
The intracellular redox environment of Staphylococcus aureus is mainly buffered by bacillithiol (BSH), a low molecular weight thiol. The identity of enzymes responsible for the recycling of oxidized bacillithiol disulfide (BSSB) to the reduced form (BSH) remains elusive. We examined YpdA, a putative bacillithiol reductase, for its role in maintaining intracellular redox homeostasis. The ypdA mutant showed increased levels of BSSB and a lower bacillithiol redox ratio vs. the isogenic parent, indicating a higher level of oxidative stress within the bacterial cytosol. We showed that YpdA consumed NAD(P)H; and YpdA protein levels were augmented in response to stress. Wild type strains overexpressing YpdA showed increased tolerance to oxidants and electrophilic agents. Importantly, YpdA overexpression in the parental strain caused an increase in BSH levels accompanied by a decrease in BSSB concentration in the presence of stress, resulting in an increase in bacillithiol redox ratio vs. the vector control. Additionally, the ypdA mutant exhibited decreased survival in human neutrophils (PMNs) as compared with the parent, while YpdA overexpression protected the resulting strain from oxidative stress in vitro and from killing by human neutrophils ex vivo. Taken together, these data present a new role for YpdA in S. aureus physiology and virulence through the bacillithiol system.
Collapse
Affiliation(s)
- Irina V Mikheyeva
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Jason M Thomas
- Biology Department, California State University, Fresno, Fresno, CA 93740, USA
| | - Stacey L Kolar
- Department of Pediatrics, Cedars Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Anna-Rita Corvaglia
- Genomic Research Laboratory, Service of Infectious Diseases, University Hospital of Geneva, 1205 Geneva 4, Switzerland
| | - Nadia Gaϊa
- Genomic Research Laboratory, Service of Infectious Diseases, University Hospital of Geneva, 1205 Geneva 4, Switzerland
| | - Stefano Leo
- Genomic Research Laboratory, Service of Infectious Diseases, University Hospital of Geneva, 1205 Geneva 4, Switzerland
| | - Patrice Francois
- Genomic Research Laboratory, Service of Infectious Diseases, University Hospital of Geneva, 1205 Geneva 4, Switzerland
| | - George Y Liu
- Department of Pediatrics, Cedars Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Mamta Rawat
- Biology Department, California State University, Fresno, Fresno, CA 93740, USA
| | - Ambrose L Cheung
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| |
Collapse
|
37
|
Watanabe T, Yamamoto Y, Miura M, Konno H, Yano S, Nonomura Y. Systematic Analysis of Selective Bactericidal Activity of Fatty Acids against Staphylococcus aureus with Minimum Inhibitory Concentration and Minimum Bactericidal Concentration. J Oleo Sci 2019; 68:291-296. [PMID: 30760667 DOI: 10.5650/jos.ess18220] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Bacterial flora on the skin surface contains Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis) which causes rough skin and atopic dermatitis and enhances innate immunity, respectively. In this study, minimum inhibitory concentration (MIC) was evaluated for six saturated fatty acids and two unsaturated fatty acids against S. aureus and S. epidermidis. The antimicrobial behavior in the liquid medium was categorized into three groups. The first was the selective antibacterial activity group comprising myristic acid (C14:0 fatty acid), palmitoleic acid (C16:1 fatty acid), and oleic acid (C18:1 fatty acid) and preferentially displayed antimicrobial activity for S. aureus (group 1). C16:1 fatty acid displayed high antimicrobial activity only for S. aureus. The second was the non-selective antibacterial activity group which displayed antibacterial activity for both Staphylococci (group 2). Caprylic acid (C8:0 fatty acid), capric acid (C10:0 fatty acid), and lauric acid (C12:0 fatty acid) comprised group 2. The third was the nonantibacterial activity group which did not show significant antimicrobial activity (group 3). Bactericidal activities were confirmed for C12:0 fatty acid and C16:1 fatty acid by evaluating the minimum bactericidal concentration (MBC) on the agar medium. C12:0 fatty acid displayed non-selective bactericidal behavior against S. aureus and S. epidermidis when the fatty acid concentration was above 250 μg mL-1. These findings suggest that C16:1 fatty acid has the potential to be used as a detergent in skin care and medical products because it can selectively kill only S. aureus.
Collapse
Affiliation(s)
- Takamasa Watanabe
- Department of Biochemical Engineering, Graduate School of Science and Engineering, Yamagata University
| | - Yoshiaki Yamamoto
- Department of Biochemical Engineering, Graduate School of Science and Engineering, Yamagata University
| | - Maki Miura
- Department of Biochemical Engineering, Graduate School of Science and Engineering, Yamagata University
| | - Hiroyuki Konno
- Department of Biochemical Engineering, Graduate School of Science and Engineering, Yamagata University
| | - Shigekazu Yano
- Department of Biochemical Engineering, Graduate School of Science and Engineering, Yamagata University
| | - Yoshimune Nonomura
- Department of Biochemical Engineering, Graduate School of Science and Engineering, Yamagata University
| |
Collapse
|
38
|
Baptista I, Santos M, Rudnitskaya A, Saraiva JA, Almeida A, Rocha SM. A comprehensive look into the volatile exometabolome of enteroxic and non-enterotoxic Staphylococcus aureus strains. Int J Biochem Cell Biol 2019; 108:40-50. [PMID: 30648622 DOI: 10.1016/j.biocel.2019.01.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 11/06/2018] [Accepted: 01/11/2019] [Indexed: 01/08/2023]
Abstract
Staphylococcal food poisoning is a disease that originates significant health and economic losses and is caused by Staphylococcus aureus strains able to produce enterotoxins. The aim of this work is to go further on the study of the volatile exometabolome of S. aureus using an advanced gas chromatographic technique. Enterotoxic and non-enterotoxic strains were assessed. The volatile exometabolome profile comprised 240 volatiles belonging to ten chemical families. This volatiles were mainly by-products of branched-chain amino acids and methionine degradation, pyruvate metabolism, diacetyl pathway, oxidative stress and carotenoid cleavage. Metabolites released by the first two pathways were produced in higher contents by the enterotoxic strains. This study add further insights to S. aureus volatile exometabolome, and also shows that by applying it, it is possible to distinguish strains of S. aureus by the number of produced enterotoxins, which is especially important from the food safety point of view.
Collapse
Affiliation(s)
- Inês Baptista
- Department of Biology and CESAM, University of Aveiro, 3810-193, Aveiro, Portugal; Department of Chemistry and QOPNA, University of Aveiro, 3810-193, Aveiro, Portugal.
| | - Magda Santos
- Department of Chemistry and QOPNA, University of Aveiro, 3810-193, Aveiro, Portugal.
| | - Alisa Rudnitskaya
- Department of Chemistry and CESAM, University of Aveiro, 3810-193, Aveiro, Portugal.
| | - Jorge A Saraiva
- Department of Chemistry and QOPNA, University of Aveiro, 3810-193, Aveiro, Portugal.
| | - Adelaide Almeida
- Department of Biology and CESAM, University of Aveiro, 3810-193, Aveiro, Portugal.
| | - Sílvia M Rocha
- Department of Chemistry and QOPNA, University of Aveiro, 3810-193, Aveiro, Portugal.
| |
Collapse
|
39
|
Zhou C, Bhinderwala F, Lehman MK, Thomas VC, Chaudhari SS, Yamada KJ, Foster KW, Powers R, Kielian T, Fey PD. Urease is an essential component of the acid response network of Staphylococcus aureus and is required for a persistent murine kidney infection. PLoS Pathog 2019; 15:e1007538. [PMID: 30608981 PMCID: PMC6343930 DOI: 10.1371/journal.ppat.1007538] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 01/23/2019] [Accepted: 12/18/2018] [Indexed: 01/22/2023] Open
Abstract
Staphylococcus aureus causes acute and chronic infections resulting in significant morbidity. Urease, an enzyme that generates NH3 and CO2 from urea, is key to pH homeostasis in bacterial pathogens under acidic stress and nitrogen limitation. However, the function of urease in S. aureus niche colonization and nitrogen metabolism has not been extensively studied. We discovered that urease is essential for pH homeostasis and viability in urea-rich environments under weak acid stress. The regulation of urease transcription by CcpA, Agr, and CodY was identified in this study, implying a complex network that controls urease expression in response to changes in metabolic flux. In addition, it was determined that the endogenous urea derived from arginine is not a significant contributor to the intracellular nitrogen pool in non-acidic conditions. Furthermore, we found that during a murine chronic renal infection, urease facilitates S. aureus persistence by promoting bacterial fitness in the low-pH, urea-rich kidney. Overall, our study establishes that urease in S. aureus is not only a primary component of the acid response network but also an important factor required for persistent murine renal infections. Urease has been reported to be crucial to bacteria in environmental adaptation, virulence, and defense against host immunity. Although the function of urease in S. aureus is not clear, recent evidence suggests that urease is important for acid resistance in various niches. Our study deciphered a function of S. aureus urease both in laboratory conditions and during host colonization. Furthermore, we uncovered the major components of the regulatory system that fine-tunes the expression of urease. Collectively, this study established the dual function of urease which serves as a significant part of the S. aureus acid response while also serving as an enzyme required for persistent kidney infections and potential subsequent staphylococcal metastasis.
Collapse
Affiliation(s)
- Chunyi Zhou
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Fatema Bhinderwala
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
- Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
| | - McKenzie K. Lehman
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Vinai C. Thomas
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Sujata S. Chaudhari
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Kelsey J. Yamada
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Kirk W. Foster
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Robert Powers
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
- Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Paul D. Fey
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
- * E-mail:
| |
Collapse
|
40
|
Darisipudi MN, Nordengrün M, Bröker BM, Péton V. Messing with the Sentinels-The Interaction of Staphylococcus aureus with Dendritic Cells. Microorganisms 2018; 6:microorganisms6030087. [PMID: 30111706 PMCID: PMC6163568 DOI: 10.3390/microorganisms6030087] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/12/2018] [Accepted: 08/14/2018] [Indexed: 12/14/2022] Open
Abstract
Staphylococcus aureus (S. aureus) is a dangerous pathogen as well as a frequent colonizer, threatening human health worldwide. Protection against S. aureus infection is challenging, as the bacteria have sophisticated strategies to escape the host immune response. To maintain equilibrium with S. aureus, both innate and adaptive immune effector mechanisms are required. Dendritic cells (DCs) are critical players at the interface between the two arms of the immune system, indispensable for inducing specific T cell responses. In this review, we highlight the importance of DCs in mounting innate as well as adaptive immune responses against S. aureus with emphasis on their role in S. aureus-induced respiratory diseases. We also review what is known about mechanisms that S. aureus has adopted to evade DCs or manipulate these cells to its advantage.
Collapse
Affiliation(s)
- Murthy N Darisipudi
- Department of Immunology, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße DZ7, D-17475 Greifswald, Germany.
| | - Maria Nordengrün
- Department of Immunology, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße DZ7, D-17475 Greifswald, Germany.
| | - Barbara M Bröker
- Department of Immunology, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße DZ7, D-17475 Greifswald, Germany.
| | - Vincent Péton
- Department of Immunology, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße DZ7, D-17475 Greifswald, Germany.
| |
Collapse
|
41
|
Lentz CS, Sheldon JR, Crawford LA, Cooper R, Garland M, Amieva MR, Weerapana E, Skaar EP, Bogyo M. Identification of a S. aureus virulence factor by activity-based protein profiling (ABPP). Nat Chem Biol 2018; 14:609-617. [PMID: 29769740 PMCID: PMC6202179 DOI: 10.1038/s41589-018-0060-1] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 03/27/2018] [Indexed: 12/22/2022]
Abstract
Serine hydrolases play diverse roles in regulating host-pathogen interactions in a number of organisms, yet few have been characterized in the human pathogen Staphylococcus aureus. Here we describe a chemical proteomic screen that identified ten previously uncharacterized S. aureus serine hydrolases that mostly lack human homologs. We termed these enzymes fluorophosphonate-binding hydrolases (FphA-J). One hydrolase, FphB, can process short fatty acid esters, exhibits increased activity in response to host cell factors, is located predominantly on the bacterial cell surface in a subset of cells, and is concentrated in the division septum. Genetic disruption of fphB confirmed that the enzyme is dispensable for bacterial growth in culture but crucial for establishing infection in distinct sites in vivo. A selective small molecule inhibitor of FphB effectively reduced infectivity in vivo, suggesting that it may be a viable therapeutic target for the treatment or management of Staphylococcus infections.
Collapse
Affiliation(s)
- Christian S Lentz
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA
| | - Jessica R Sheldon
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lisa A Crawford
- Department of Chemistry, Boston College, Chestnut Hill, MA, USA
| | - Rachel Cooper
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, USA
| | - Megan Garland
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA
| | - Manuel R Amieva
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, USA
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Eric P Skaar
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Matthew Bogyo
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA.
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA.
| |
Collapse
|
42
|
Castillo H, Li X, Schilkey F, Smith GB. Transcriptome analysis reveals a stress response of Shewanella oneidensis deprived of background levels of ionizing radiation. PLoS One 2018; 13:e0196472. [PMID: 29768440 PMCID: PMC5955497 DOI: 10.1371/journal.pone.0196472] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 04/13/2018] [Indexed: 11/21/2022] Open
Abstract
Natural ionizing background radiation has exerted a constant pressure on organisms since the first forms of life appeared on Earth, so that cells have developed molecular mechanisms to avoid or repair damages caused directly by radiation or indirectly by radiation-induced reactive oxygen species (ROS). In the present study, we investigated the transcriptional effect of depriving Shewanella oneidensis cultures of background levels of radiation by growing the cells in a mine 655 m underground, thus reducing the dose rate from 72.1 to 0.9 nGy h-1 from control to treatment, respectively. RNASeq transcriptome analysis showed the differential expression of 4.6 and 7.6% of the S. oneidensis genome during early- and late-exponential phases of growth, respectively. The greatest change observed in the treatment was the downregulation of ribosomal proteins (21% of all annotated ribosomal protein genes during early- and 14% during late-exponential) and tRNA genes (14% of all annotated tRNA genes in early-exponential), indicating a marked decrease in protein translation. Other significant changes were the upregulation of membrane transporters, implying an increase in the traffic of substrates across the cell membrane, as well as the up and downregulation of genes related to respiration, which could be interpreted as a response to insufficient oxidants in the cells. In other reports, there is evidence in multiple species that some ROS not just lead to oxidative stress, but act as signaling molecules to control cellular metabolism at the transcriptional level. Consistent with these reports, several genes involved in the metabolism of carbon and biosynthesis of amino acids were also regulated, lending support to the idea of a wide metabolic response. Our results indicate that S. oneidensis is sensitive to the withdrawal of background levels of ionizing radiation and suggest that a transcriptional response is required to maintain homeostasis and retain normal growth.
Collapse
Affiliation(s)
- Hugo Castillo
- Department of Biology, New Mexico State University, Las Cruces, NM, United States of America
| | - Xiaoping Li
- Department of Botany and Plant Pathology, Oregon State University, Hermiston, OR, United States of America
| | - Faye Schilkey
- National Center for Genome Resources, Santa Fe, NM, United States of America
| | - Geoffrey B Smith
- Department of Biology, New Mexico State University, Las Cruces, NM, United States of America
| |
Collapse
|
43
|
Guerrero-Castro J, Lozano L, Sohlenkamp C. Dissecting the Acid Stress Response of Rhizobium tropici CIAT 899. Front Microbiol 2018; 9:846. [PMID: 29760688 PMCID: PMC5936775 DOI: 10.3389/fmicb.2018.00846] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 04/12/2018] [Indexed: 11/27/2022] Open
Abstract
Rhizobium tropici CIAT899 is a nodule-forming α-proteobacterium displaying intrinsic resistance to several abiotic stress conditions such as low pH and high temperatures, which are common in tropical environments. It is a good competitor for Phaseolus vulgaris (common bean) nodule occupancy at low pH values, however little is known about the genetic and physiological basis of the tolerance to acidic conditions. To identify genes in R. tropici involved in pH stress response we combined two different approaches: (1) A Tn5 mutant library of R. tropici CIAT899 was screened and 26 acid-sensitive mutants were identified. For 17 of these mutants, the transposon insertion sites could be identified. (2) We also studied the transcriptomes of cells grown under different pH conditions using RNA-Seq. RNA was extracted from cells grown for several generations in minimal medium at 6.8 or 4.5 (adapted cells). In addition, we acid-shocked cells pre-grown at pH 6.8 for 45 min at pH 4.5. Of the 6,289 protein-coding genes annotated in the genome of R. tropici CIAT 899, 383 were differentially expressed under acidic conditions (pH 4.5) vs. control condition (pH 6.8). Three hundred and fifty one genes were induced and 32 genes were repressed; only 11 genes were induced upon acid shock. The acid stress response of R. tropici CIAT899 is versatile: we found genes encoding response regulators and membrane transporters, enzymes involved in amino acid and carbohydrate metabolism and proton extrusion, in addition to several hypothetical genes. Our findings enhance our understanding of the core genes that are important during the acid stress response in R. tropici.
Collapse
Affiliation(s)
- Julio Guerrero-Castro
- Programa de Ecología Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico.,Programa de Doctorado en Ciencias Biomédicas, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Luis Lozano
- Programa de Genómica Evolutiva, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Christian Sohlenkamp
- Programa de Ecología Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| |
Collapse
|
44
|
McClary JS, Boehm AB. Transcriptional Response of Staphylococcus aureus to Sunlight in Oxic and Anoxic Conditions. Front Microbiol 2018; 9:249. [PMID: 29599752 PMCID: PMC5863498 DOI: 10.3389/fmicb.2018.00249] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 01/31/2018] [Indexed: 12/20/2022] Open
Abstract
The transcriptional response of Staphylococcus aureus strain Newman to sunlight exposure was investigated under both oxic and anoxic conditions using RNA sequencing to gain insight into potential mechanisms of inactivation. S. aureus is a pathogenic bacterium detected at recreational beaches which can cause gastrointestinal illness and skin infections, and is of increasing public health concern. To investigate the S. aureus photostress response in oligotrophic seawater, S. aureus cultures were suspended in seawater and exposed to full spectrum simulated sunlight. Experiments were performed under oxic or anoxic conditions to gain insight into the effects of oxygen-mediated and non-oxygen-mediated inactivation mechanisms. Transcript abundance was measured after 6 h of sunlight exposure using RNA sequencing and was compared to transcript abundance in paired dark control experiments. Culturable S. aureus decayed following biphasic inactivation kinetics with initial decay rate constants of 0.1 and 0.03 m2 kJ−1 in oxic and anoxic conditions, respectively. RNA sequencing revealed that 71 genes had different transcript abundance in the oxic sunlit experiments compared to dark controls, and 18 genes had different transcript abundance in the anoxic sunlit experiments compared to dark controls. The majority of genes showed reduced transcript abundance in the sunlit experiments under both conditions. Three genes (ebpS, NWMN_0867, and NWMN_1608) were found to have the same transcriptional response to sunlight between both oxic and anoxic conditions. In the oxic condition, transcripts associated with porphyrin metabolism, nitrate metabolism, and membrane transport functions were increased in abundance during sunlight exposure. Results suggest that S. aureus responds differently to oxygen-dependent and oxygen-independent photostress, and that endogenous photosensitizers play an important role during oxygen-dependent indirect photoinactivation.
Collapse
Affiliation(s)
- Jill S McClary
- Civil and Environmental Engineering, Stanford University, Stanford, CA, United States
| | - Alexandria B Boehm
- Civil and Environmental Engineering, Stanford University, Stanford, CA, United States
| |
Collapse
|
45
|
Effect of preliminary stresses on the resistance of Escherichia coli and Staphylococcus aureus toward non-thermal plasma (NTP) challenge. Food Res Int 2017; 105:178-183. [PMID: 29433205 DOI: 10.1016/j.foodres.2017.11.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Revised: 11/05/2017] [Accepted: 11/13/2017] [Indexed: 11/27/2022]
Abstract
As the development of hurdle technology, cross-protection of various stresses for pathogens posed the potential risk to food safety and public health. This study tried to explore various preliminary stresses including acidity, osmosis, oxidation, heat and cold on the resistance of microbial cells toward the non-thermal plasma (NTP) exposure. The results indicated that short-term (4h) exposure of Staphylococcus aureus and Escherichia coli to acidity, osmosis, oxidation, heat and cold stresses did not lead to the resistance to the subsequent NTP treatment. On the contrary, acidity, osmosis and heat preadaptation increased the vulnerability of E. coli cells to NTP treatment. After exposing S. aureus to osmosis, oxidation, heat and cold stress for longer period (24h), the reduction level showed significantly (P<0.05) higher. Interestingly, long-term (24h) preliminary exposure of acidic stress exhibited protective effect for S. aureus against the following NTP exposure with less damage in cell membrane integrity, membrane potential and intracellular enzyme activity. It might be due to the protein production for oxidative stress response during preliminary acidic adaptation. In general, the obtained result helped to grasp better understanding of the microbial stress response to NTP treatment and provided insight for the future research in order to accelerate the development of NTP technology in food industry.
Collapse
|
46
|
Vibrational spectroscopy combined with transcriptomic analysis for investigation of bacterial responses towards acid stress. Appl Microbiol Biotechnol 2017; 102:333-343. [DOI: 10.1007/s00253-017-8561-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 09/21/2017] [Accepted: 09/27/2017] [Indexed: 11/26/2022]
|
47
|
Uribe-Querol E, Rosales C. Control of Phagocytosis by Microbial Pathogens. Front Immunol 2017; 8:1368. [PMID: 29114249 PMCID: PMC5660709 DOI: 10.3389/fimmu.2017.01368] [Citation(s) in RCA: 141] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Accepted: 10/05/2017] [Indexed: 12/17/2022] Open
Abstract
Phagocytosis is a fundamental process of cells to capture and ingest foreign particles. Small unicellular organisms such as free-living amoeba use this process to acquire food. In pluricellular organisms, phagocytosis is a universal phenomenon that all cells are able to perform (including epithelial, endothelial, fibroblasts, etc.), but some specialized cells (such as neutrophils and macrophages) perform this very efficiently and were therefore named professional phagocytes by Rabinovitch. Cells use phagocytosis to capture and clear all particles larger than 0.5 µm, including pathogenic microorganisms and cellular debris. Phagocytosis involves a series of steps from recognition of the target particle, ingestion of it in a phagosome (phagocytic vacuole), maturation of this phagosome into a phagolysosome, to the final destruction of the ingested particle in the robust antimicrobial environment of the phagolysosome. For the most part, phagocytosis is an efficient process that eliminates invading pathogens and helps maintaining homeostasis. However, several pathogens have also evolved different strategies to prevent phagocytosis from proceeding in a normal way. These pathogens have a clear advantage to perpetuate the infection and continue their replication. Here, we present an overview of the phagocytic process with emphasis on the antimicrobial elements professional phagocytes use. We also summarize the current knowledge on the microbial strategies different pathogens use to prevent phagocytosis either at the level of ingestion, phagosome formation, and maturation, and even complete escape from phagosomes.
Collapse
Affiliation(s)
- Eileen Uribe-Querol
- División de Estudios de Posgrado e Investigación, Facultad de Odontología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Carlos Rosales
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico
| |
Collapse
|
48
|
Jia K, Wang G, Liang L, Wang M, Wang H, Xu X. Preliminary Transcriptome Analysis of Mature Biofilm and Planktonic Cells of Salmonella Enteritidis Exposure to Acid Stress. Front Microbiol 2017; 8:1861. [PMID: 29018430 PMCID: PMC5622974 DOI: 10.3389/fmicb.2017.01861] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 09/12/2017] [Indexed: 11/13/2022] Open
Abstract
Salmonella has emerged as a well-recognized food-borne pathogen, with many strains able to form biofilms and thus cause cross-contamination in food processing environments where acid-based disinfectants are widely encountered. In the present study, RNA sequencing was employed to establish complete transcriptome profiles of Salmonella Enteritidis in the forms of planktonic and biofilm-associated cells cultured in Tryptic Soytone Broth (TSB) and acidic TSB (aTSB). The gene expression patterns of S. Enteritidis significantly differed between biofilm-associated and planktonic cells cultivated under the same conditions. The assembled transcriptome of S. Enteritidis in this study contained 5,442 assembled transcripts, including 3,877 differentially expressed genes (DEGs) identified in biofilm and planktonic cells. These DEGs were enriched in terms such as regulation of biological process, metabolic process, macromolecular complex, binding and transferase activity, which may play crucial roles in the biofilm formation of S. Enteritidis cultivated in aTSB. Three significant pathways were observed to be enriched under acidic conditions: bacterial chemotaxis, porphyrin-chlorophyll metabolism and sulfur metabolism. In addition, 15 differentially expressed novel non-coding small RNAs (sRNAs) were identified, and only one was found to be up-regulated in mature biofilms. This preliminary study of the S. Enteritidis transcriptome serves as a basis for future investigations examining the complex network systems that regulate Salmonella biofilm in acidic environments, which provide information on biofilm formation and acid stress interaction that may facilitate the development of novel disinfection procedures in the food processing industry.
Collapse
Affiliation(s)
- Kun Jia
- National Center of Meat Quality and Safety Control, Nanjing Agricultural University, Nanjing, China
| | - Guangyu Wang
- Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Nanjing Agricultural University, Nanjing, China
| | - Lijiao Liang
- National Center of Meat Quality and Safety Control, Nanjing Agricultural University, Nanjing, China
| | - Meng Wang
- National Center of Meat Quality and Safety Control, Nanjing Agricultural University, Nanjing, China
| | - Huhu Wang
- National Center of Meat Quality and Safety Control, Nanjing Agricultural University, Nanjing, China
| | - Xinglian Xu
- Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Nanjing Agricultural University, Nanjing, China
| |
Collapse
|
49
|
Shabayek S, Spellerberg B. Acid Stress Response Mechanisms of Group B Streptococci. Front Cell Infect Microbiol 2017; 7:395. [PMID: 28936424 PMCID: PMC5594096 DOI: 10.3389/fcimb.2017.00395] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 08/23/2017] [Indexed: 12/20/2022] Open
Abstract
Group B streptococcus (GBS) is a leading cause of neonatal mortality and morbidity in the United States and Europe. It is part of the vaginal microbiota in up to 30% of pregnant women and can be passed on to the newborn through perinatal transmission. GBS has the ability to survive in multiple different host niches. The pathophysiology of this bacterium reveals an outstanding ability to withstand varying pH fluctuations of the surrounding environments inside the human host. GBS host pathogen interations include colonization of the acidic vaginal mucosa, invasion of the neutral human blood or amniotic fluid, breaching of the blood brain barrier as well as survival within the acidic phagolysosomal compartment of macrophages. However, investigations on GBS responses to acid stress are limited. Technologies, such as whole genome sequencing, genome-wide transcription and proteome mapping facilitate large scale identification of genes and proteins. Mechanisms enabling GBS to cope with acid stress have mainly been studied through these techniques and are summarized in the current review
Collapse
Affiliation(s)
- Sarah Shabayek
- Institute of Medical Microbiology and Hygiene, University of UlmUlm, Germany.,Department of Microbiology and Immunology, Faculty of Pharmacy, Suez Canal UniversityIsmailia, Egypt
| | - Barbara Spellerberg
- Institute of Medical Microbiology and Hygiene, University of UlmUlm, Germany
| |
Collapse
|
50
|
Insight into the Genome of Staphylococcus xylosus, a Ubiquitous Species Well Adapted to Meat Products. Microorganisms 2017; 5:microorganisms5030052. [PMID: 28850086 PMCID: PMC5620643 DOI: 10.3390/microorganisms5030052] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 08/21/2017] [Accepted: 08/25/2017] [Indexed: 01/23/2023] Open
Abstract
Staphylococcus xylosus belongs to the vast group of coagulase-negative staphylococci. It is frequently isolated from meat products, either fermented or salted and dried, and is commonly used as starter cultures in sausage manufacturing. Analysis of the S. xylosus genome together with expression in situ in a meat model revealed that this bacterium is well adapted to meat substrates, being able to use diverse substrates as sources of carbon and energy and different sources of nitrogen. It is well-equipped with genes involved in osmotic, oxidative/nitrosative, and acidic stress responses. It is responsible for the development of the typical colour of cured meat products via its nitrate reductase activity. It contributes to sensorial properties, mainly by the the catabolism of pyruvate and amino acids resulting in odorous compounds and by the limiting of the oxidation of fatty acids, thereby avoiding rancidity.
Collapse
|