Novel insights into nickel import in Staphylococcus aureus: the positive role of free histidine and structural characterization of a new thiazolidine-type nickel chelator

Metallomics ◽  
2015 ◽  
Vol 7 (4) ◽  
pp. 613-621 ◽  
Author(s):  
H. Lebrette ◽  
E. Borezée-Durant ◽  
L. Martin ◽  
P. Richaud ◽  
E. Boeri Erba ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Structural Characterization ◽  
Growth Conditions ◽  
Positive Role ◽  
Type Nickel

Staphylococcus aureuspossesses two canonical ABC-importers dedicated to nickel acquisition: the NikABCDE and the CntABCDF systems, active under different growth conditions.

scholarly journals Role of Siderophore Biosynthesis in Virulence of Staphylococcus aureus: Identification and Characterization of Genes Involved in Production of a Siderophore

2004 ◽  
Vol 72 (1) ◽  
pp. 29-37 ◽  
Author(s):  
Suzanne E. Dale ◽  
Amanda Doherty-Kirby ◽  
Gilles Lajoie ◽  
David E. Heinrichs
Keyword(s):  
Staphylococcus Aureus ◽  
Growth Conditions ◽  
Siderophore Production ◽  
Coagulase Negative Staphylococci ◽  
Iron Restriction ◽  
Growth Deficiency ◽  
Molecular Determinants ◽  
Identification And Characterization

ABSTRACT Molecular determinants underlying the production of siderophores in the human and animal pathogen Staphylococcus aureus and the contribution of siderophore production to the virulence of this bacterium have, until now, remained undefined. Here, we show that S. aureus strains RN6390 and Newman produce siderophore when the cells are starved for iron. We further identified and characterized a nine-gene, iron-regulated operon, designated sbn and situated between sirABC and galE on the S. aureus chromosome, that is involved in the production of a siderophore. Mutation of the sbnE gene, in both RN6390 and Newman, eliminates the ability of these strains to produce a siderophore under iron-limited growth conditions, while introduction of multicopy sbnE into sbnE mutants complemented the inability of the mutants to produce the siderophore. sbnE mutants, in both the RN6390 and Newman backgrounds, displayed a drastic growth deficiency, compared to the wild type, in iron-restricted growth medium, whereas no such deficiency was observed during growth in iron-replete medium. Complemented mutants showed a restored ability to grow under iron restriction. We further showed that an sbnE mutant was compromised in a murine kidney abscess model of S. aureus infection, illustrating the importance of siderophore production to the pathogenicity of S. aureus. sbn genes were present in all S. aureus strains tested (and all S. aureus genome sequences) but were undetectable in any of the 13 coagulase-negative staphylococci tested, including Staphylococcus epidermidis.

scholarly journals Characterization of Three Small Proteins inBrucella abortusLinked to Fucose Utilization

2018 ◽  
Vol 200 (18) ◽  
Author(s):  
James A. Budnick ◽  
Lauren M. Sheehan ◽  
Lin Kang ◽  
Pawel Michalak ◽  
Clayton C. Caswell
Keyword(s):  
Brucella Abortus ◽  
Transcriptional Control ◽  
Sugar Transport ◽  
Genetic System ◽  
Growth Conditions ◽  
Content Type ◽  
Small Regulatory Rna ◽  
Small Proteins

ABSTRACTElucidating the function of proteins <50 amino acids in length is no small task. Nevertheless, small proteins can play vital roles in the lifestyle of bacteria and influence the virulence of pathogens; thus, the investigation of the small proteome is warranted. Recently, our group identified theBrucella abortusprotein VtlR as a transcriptional activator of four genes, one of which is the well-studied small regulatory RNA AbcR2, while the other three genes encode hypothetical small proteins, two of which are highly conserved among the orderRhizobiales. This study provides evidence that all three genes encode authentic small proteins and that all three are highly expressed under oxidative stress, low-pH, and stationary-phase growth conditions. Fractionation of the cells revealed that the proteins are localized to the membranes ofB. abortus. We demonstrate that the small proteins under the transcriptional control of VtlR are not accountable for attenuation observed with theB. abortusvtlRdeletion strain. However, there is an association between VtlR-regulated genes and growth inhibition in the presence of the sugarl-fucose. Subsequent transcriptomic analyses revealed thatB. abortusinitiates the transcription of a locus encoding a putative sugar transport and utilization system when the bacteria are cultured in the presence ofl-fucose. Altogether, our observations characterize the role of the VtlR-controlled small proteins BAB1_0914, BAB2_0512, and BAB2_0574 in the biology ofB. abortus, particularly in the capacity of the bacteria to utilizel-fucose.IMPORTANCEDespite being one of the most common zoonoses worldwide, there is currently no human vaccine to combat brucellosis. Therefore, a better understanding of the pathogenesis and biology ofBrucellaspp., the causative agent of brucellosis, is essential for the discovery of novel therapeutics against these highly infectious bacteria. In this study, we further characterize the virulence-associated transcriptional regulator VtlR inBrucella abortus. Our findings not only shed light on our current understanding of a virulence related genetic system inBrucellaspp. but also increase our knowledge of small proteins in the field of bacteriology.

scholarly journals PHA Production and PHA Synthases of the Halophilic Bacterium Halomonas sp. SF2003

2020 ◽  
Vol 7 (1) ◽  
pp. 29
Author(s):  
Tatiana Thomas ◽  
Kumar Sudesh ◽  
Alexis Bazire ◽  
Anne Elain ◽  
Hua Tiang Tan ◽  
...  
Keyword(s):  
Marine Bacterium ◽  
Carbon Sources ◽  
Halophilic Bacterium ◽  
Growth Conditions ◽  
In Silico Study ◽  
Carbon Substrates ◽  
Cupriavidus Necator H16 ◽  
Pha Production

Among the different tools which can be studied and managed to tailor-make polyhydroxyalkanoates (PHAs) and enhance their production, bacterial strain and carbon substrates are essential. The assimilation of carbon sources is dependent on bacterial strain’s metabolism and consequently cannot be dissociated. Both must wisely be studied and well selected to ensure the highest production yield of PHAs. Halomonas sp. SF2003 is a marine bacterium already identified as a PHA-producing strain and especially of poly-3-hydroxybutyrate (P-3HB) and poly-3-hydroxybutyrate-co-3-hydroxyvalerate (P-3HB-co-3HV). Previous studies have identified different genes potentially involved in PHA production by Halomonas sp. SF2003, including two phaC genes with atypical characteristics, phaC1 and phaC2. At the same time, an interesting adaptability of the strain in front of various growth conditions was highlighted, making it a good candidate for biotechnological applications. To continue the characterization of Halomonas sp. SF2003, the screening of carbon substrates exploitable for PHA production was performed as well as production tests. Additionally, the functionality of both PHA synthases PhaC1 and PhaC2 was investigated, with an in silico study and the production of transformant strains, in order to confirm and to understand the role of each one on PHA production. The results of this study confirm the adaptability of the strain and its ability to exploit various carbon substrates, in pure or mixed form, for PHA production. Individual expression of PhaC1 and PhaC2 synthases in a non-PHA-producing strain, Cupriavidus necator H16 PHB¯4 (DSM 541), allows obtaining PHA production, demonstrating at the same time, functionality and differences between both PHA synthases. All the results of this study confirm the biotechnological interest in Halomonas sp. SF2003.

Biochemical, Kinetic, and Computational Structural Characterization of Shikimate Kinase from Methicillin-Resistant Staphylococcus aureus

2019 ◽  
Vol 61 (4) ◽  
pp. 274-285 ◽  
Author(s):  
Alejandro Favela-Candia ◽  
Alfredo Téllez-Valencia ◽  
Mara Campos-Almazán ◽  
Erick Sierra-Campos ◽  
Mónica Valdez-Solana ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Structural Characterization ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Shikimate Kinase ◽  
Methicillin Resistant

Insights into the role of nucleotide-dependent conformational change in nitrogenase catalysis: Structural characterization of the nitrogenase Fe protein Leu127 deletion variant with bound MgATP

2006 ◽  
Vol 100 (5-6) ◽  
pp. 1041-1052 ◽  
Author(s):  
Sanchayita Sen ◽  
Arathi Krishnakumar ◽  
Jammi McClead ◽  
Michael K. Johnson ◽  
Lance C. Seefeldt ◽  
...  
Keyword(s):  
Conformational Change ◽  
Structural Characterization ◽  
Deletion Variant ◽  
Fe Protein
Sign in / Sign up

Export Citation Format

Share Document