scholarly journals Phosphoglucomutase of Yersinia pestis Is Required for Autoaggregation and Polymyxin B Resistance

2009 ◽  
Vol 78 (3) ◽  
pp. 1163-1175 ◽  
Author(s):  
Suleyman Felek ◽  
Artur Muszyński ◽  
Russell W. Carlson ◽  
Tiffany M. Tsang ◽  
B. Joseph Hinnebusch ◽  
...  
Keyword(s):  
Antimicrobial Peptide ◽  
Yersinia Pestis ◽  
Polymyxin B ◽  
Surface Structures ◽  
Tandem Ms ◽  
Gene Encoding ◽  
Targeted Deletion ◽  
Transposon Insertion ◽  
Increased Sensitivity ◽  
Antimicrobial Peptide Resistance

ABSTRACT Yersinia pestis, the causative agent of plague, autoaggregates within a few minutes of cessation of shaking when grown at 28°C. To identify the autoaggregation factor of Y. pestis, we performed mariner-based transposon mutagenesis. Autoaggregation-defective mutants from three different pools were identified, each with a transposon insertion at a different position within the gene encoding phosphoglucomutase (pgmA; y1258). Targeted deletion of pgmA in Y. pestis KIM5 also resulted in loss of autoaggregation. Given the previously defined role for phosphoglucomutase in antimicrobial peptide resistance in other organisms, we tested the KIM5 ΔpgmA mutant for antimicrobial peptide sensitivity. The ΔpgmA mutant displayed >1,000-fold increased sensitivity to polymyxin B compared to the parental Y. pestis strain, KIM5. This sensitivity is not due to changes in lipopolysaccharide (LPS) since the LPSs from both Y. pestis KIM5 and the ΔpgmA mutant are identical based on a comparison of their structures by mass spectrometry (MS), tandem MS, and nuclear magnetic resonance analyses. Furthermore, the ability of polymyxin B to neutralize LPS toxicity was identical for LPS purified from both KIM5 and the ΔpgmA mutant. Our results indicate that increased polymyxin B sensitivity of the ΔpgmA mutant is due to changes in surface structures other than LPS. Experiments with mice via the intravenous and intranasal routes did not demonstrate any virulence defect for the ΔpgmA mutant, nor was flea colonization or blockage affected. Our findings suggest that the activity of PgmA results in modification and/or elaboration of a surface component of Y. pestis responsible for autoaggregation and polymyxin B resistance.

scholarly journals An iron-regulated LysR-type element mediates antimicrobial peptide resistance and virulence in Yersinia pseudotuberculosis

Microbiology ◽  
2009 ◽  
Vol 155 (7) ◽  
pp. 2168-2181 ◽  
Author(s):  
Sonia Arafah ◽  
Marie-Laure Rosso ◽  
Linda Rehaume ◽  
Robert E. W. Hancock ◽  
Michel Simonet ◽  
...  
Keyword(s):  
Antimicrobial Peptide ◽  
Yersinia Pseudotuberculosis ◽  
Polymyxin B ◽  
Uptake System ◽  
Mesenteric Lymph Nodes ◽  
Iron Starvation ◽  
Iron Deprivation ◽  
Genes Encoding ◽  
Antimicrobial Peptide Resistance

During the course of its infection of the mammalian digestive tract, the entero-invasive, Gram-negative bacterium Yersinia pseudotuberculosis must overcome various hostile living conditions (notably, iron starvation and the presence of antimicrobial compounds produced in situ). We have previously reported that in vitro bacterial growth during iron deprivation raises resistance to the antimicrobial peptide polymyxin B; here, we show that this phenotype is mediated by a chromosomal gene (YPTB0333) encoding a transcriptional regulator from the LysR family. We determined that the product of YPTB0333 is a pleiotropic regulator which controls (in addition to its own expression) genes encoding the Yfe iron-uptake system and polymyxin B resistance. Lastly, by using a mouse model of oral infection, we demonstrated that YPTB0333 is required for colonization of Peyer's patches and mesenteric lymph nodes by Y. pseudotuberculosis.

scholarly journals A Protein Important for Antimicrobial Peptide Resistance, YdeI/OmdA, Is in the Periplasm and Interacts with OmpD/NmpC

2009 ◽  
Vol 191 (23) ◽  
pp. 7243-7252 ◽  
Author(s):  
M. Carolina Pilonieta ◽  
Kimberly D. Erickson ◽  
Robert K. Ernst ◽  
Corrella S. Detweiler
Keyword(s):  
Gene Expression ◽  
Antimicrobial Peptide ◽  
Bacterial Resistance ◽  
Cell Types ◽  
Polymyxin B ◽  
Sensor Kinase ◽  
Multiple Cell ◽  
Ob Fold ◽  
Antimicrobial Peptide Resistance ◽  
Multicellular Organisms

ABSTRACT Antimicrobial peptides (AMPs) kill or prevent the growth of microbes. AMPs are made by virtually all single and multicellular organisms and are encountered by bacteria in diverse environments, including within a host. Bacteria use sensor-kinase systems to respond to AMPs or damage caused by AMPs. Salmonella enterica deploys at least three different sensor-kinase systems to modify gene expression in the presence of AMPs: PhoP-PhoQ, PmrA-PmrB, and RcsB-RcsC-RcsD. The ydeI gene is regulated by the RcsB-RcsC-RcsD pathway and encodes a 14-kDa predicted oligosaccharide/oligonucleotide binding-fold (OB-fold) protein important for polymyxin B resistance in broth and also for virulence in mice. We report here that ydeI is additionally regulated by the PhoP-PhoQ and PmrA-PmrB sensor-kinase systems, which confer resistance to cationic AMPs by modifying lipopolysaccharide (LPS). ydeI, however, is not important for known LPS modifications. Two independent biochemical methods found that YdeI copurifies with OmpD/NmpC, a member of the trimeric β-barrel outer membrane general porin family. Genetic analysis indicates that ompD contributes to polymyxin B resistance, and both ydeI and ompD are important for resistance to cathelicidin antimicrobial peptide, a mouse AMP produced by multiple cell types and expressed in the gut. YdeI localizes to the periplasm, where it could interact with OmpD. A second predicted periplasmic OB-fold protein, YgiW, and OmpF, another general porin, also contribute to polymyxin B resistance. Collectively, the data suggest that periplasmic OB-fold proteins can interact with porins to increase bacterial resistance to AMPs.

scholarly journals Identification of a Genetic Locus Responsible for Antimicrobial Peptide Resistance inClostridium difficile

2010 ◽  
Vol 79 (1) ◽  
pp. 167-176 ◽  
Author(s):  
Shonna M. McBride ◽  
Abraham L. Sonenshein
Keyword(s):  
Antimicrobial Peptides ◽  
Antimicrobial Peptide ◽  
Abc Transporter ◽  
Genetic Locus ◽  
Polymyxin B ◽  
Transcriptional Analysis ◽  
Cationic Antimicrobial Peptide ◽  
Low Levels ◽  
Antimicrobial Peptide Resistance ◽  
Abc Transporter Genes

ABSTRACTClostridium difficilecauses chronic intestinal disease, yet little is understood about how the bacterium interacts with and survives in the host. To colonize the intestine and cause persistent disease, the bacterium must circumvent killing by host innate immune factors, such as cationic antimicrobial peptides (CAMPs). In this study, we investigated the effect of model CAMPs on growth and found thatC. difficileis not only sensitive to these compounds but also responds to low levels of CAMPs by expressing genes that lead to CAMP resistance. By plating the bacterium on medium containing the CAMP nisin, we isolated a mutant capable of growing in three times the inhibitory concentration of CAMPs. This mutant also showed increased resistance to the CAMPs gallidermin and polymyxin B, demonstrating tolerance to different types of antimicrobial peptides. We identified the mutated gene responsible for the resistance phenotype as CD1352. This gene encodes a putative orphan histidine kinase that lies adjacent to a predicted ABC transporter operon (CD1349 to CD1351). Transcriptional analysis of the ABC transporter genes revealed that this operon was upregulated in the presence of nisin in wild-type cells and was more highly expressed in the CD1352 mutant. The insertional disruption of the CD1349 gene resulted in significant decreases in resistance to the CAMPs nisin and gallidermin but not polymyxin B. Because of their role in cationic antimicrobial peptide resistance, we propose the designationcprABCfor genes CD1349 to CD1351 andcprKfor the CD1352 gene. These results provide the first evidence of aC. difficilegene associated with antimicrobial peptide resistance.

Potential Antimicrobial Peptides Elucidation From The Marine Bacteria

2020 ◽  
Vol 18 ◽  
Author(s):  
Adyasa Barik ◽  
Pandiyan Rajesh ◽  
Manthiram Malathi ◽  
Vellaisamy Balasubramanian
Keyword(s):  
Antimicrobial Peptide ◽  
Marine Bacteria ◽  
Unnatural Amino Acids ◽  
Wide Spectrum ◽  
Drug Resistant ◽  
Medical Field ◽  
The World ◽  
Pathogenic Microbes ◽  
Antimicrobial Peptide Resistance ◽  
Significant Attention

: In recent years, over use of antibiotics has been raising its head to a serious problem all around the world as pathogens become drug resistant and create challenges to the medical field. This failure of most potent antibiotics that kill pathogens increases the thirst for research to look further way of killing pathogens. It has been led to the findings of antimicrobial peptide which is the most potent peptide to destroy pathogens. This review gives special emphasis to the usage of marine bacteria and other microorganisms for antimicrobial peptide (AMP) which are eco friendly as well as a developing class of natural and synthetic peptides with a wide spectrum of targets to pathogenic microbes. Consequently, a significant attention has been paid mainly to (i) the structure and types of anti microbial peptides and (ii) mode of action and mechanism of antimicrobial peptide resistance to pathogens. In addition to this, the designing of AMPs has been analysed thoroughly for reducing toxicity and developing better potent AMP. It has been done by the modified unnatural amino acids by amidation to target the control of biofilm and persister cell.

scholarly journals Two distinct pathways can control expression of the gene encoding the Drosophila antimicrobial peptide metchnikowin

1998 ◽  
Vol 278 (3) ◽  
pp. 515-527 ◽  
Author(s):  
Elena A Levashina ◽  
Serge Ohresser ◽  
Bruno Lemaitre ◽  
Jean-Luc Imler
Keyword(s):  
Antimicrobial Peptide ◽  
Gene Encoding

scholarly journals A K+ Uptake Protein, TrkA, Is Required for Serum, Protamine, and Polymyxin B Resistance in Vibrio vulnificus

2004 ◽  
Vol 72 (2) ◽  
pp. 629-636 ◽  
Author(s):  
Yu-Chung Chen ◽  
Yin-Ching Chuang ◽  
Chun-Chin Chang ◽  
Chii-Ling Jeang ◽  
Ming-Chung Chang
Keyword(s):  
Human Serum ◽  
Vibrio Vulnificus ◽  
Polymyxin B ◽  
Wild Type ◽  
Gene Encoding ◽  
Reading Frame ◽  
Isogenic Mutant ◽  
Virulence Attenuation ◽  
Insertional Inactivation ◽  
Transposon Mutants

ABSTRACT Vibrio vulnificus, a highly virulent marine bacterium, is the causative agent of both serious wound infections and fatal septicemia in many areas of the world. To identify the genes required for resistance to human serum, we constructed a library of transposon mutants of V. vulnificus and screened them for hypersensitivity to human serum. Here we report that one of the isolated serum-susceptible mutants had a mutation in an open reading frame identified as trkA, a gene encoding an amino acid sequence showing high identity to that of TrkA of Vibrio alginolyticus, a protein required for the uptake of potassium. A trkA isogenic mutant was constructed via insertional inactivation, and it was significantly more easily killed by human serum, protamine, or polymyxin B than was the wild type. At K+ concentrations of 1 to 20 mM, this isogenic mutant showed attenuated growth compared to the wild-type strain. In addition, infection experiments demonstrated virulence attenuation when this mutant was administered intraperitoneally or subcutaneously to both normal and iron-treated mice, indicating that TrkA may modulate the transport of potassium and resistance to host innate defenses and that it is important for virulence in mice.

Aminoarabinose is essential for lipopolysaccharide export and intrinsic antimicrobial peptide resistance inBurkholderia cenocepacia†

2012 ◽  
Vol 85 (5) ◽  
pp. 962-974 ◽  
Author(s):  
Mohamad A. Hamad ◽  
Flaviana Di Lorenzo ◽  
Antonio Molinaro ◽  
Miguel A. Valvano
Keyword(s):  
Antimicrobial Peptide ◽  
Antimicrobial Peptide Resistance
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