Efficient preparation and metal specificity of the regulatory protein TroR from the human pathogen Treponema pallidum

Metallomics ◽  
2013 ◽  
Vol 5 (10) ◽  
pp. 1448 ◽  
Author(s):  
Yi Liu ◽  
Wei Li ◽  
Yaozhu Wei ◽  
Yindi Jiang ◽  
Xiangshi Tan
Keyword(s):  
Regulatory Protein ◽  
Treponema Pallidum ◽  
Human Pathogen ◽  
Metal Specificity

scholarly journals RocA Binds CsrS To Modulate CsrRS-Mediated Gene Regulation in Group A Streptococcus

mBio ◽  
2019 ◽  
Vol 10 (4) ◽  
Author(s):  
Nicola N. Lynskey ◽  
Jorge J. Velarde ◽  
Meredith B. Finn ◽  
Simon L. Dove ◽  
Michael R. Wessels
Keyword(s):  
Gene Regulation ◽  
Target Genes ◽  
Response Regulator ◽  
Critical Role ◽  
Regulatory Protein ◽  
Regulatory System ◽  
Fine Tuning ◽  
Human Pathogen ◽  
Two Component ◽  
Group A

ABSTRACT The orphan regulator RocA plays a critical role in the colonization and pathogenesis of the obligate human pathogen group A Streptococcus. Despite multiple lines of evidence supporting a role for RocA as an auxiliary regulator of the control of virulence two-component regulatory system CsrRS (or CovRS), the mechanism of action of RocA remains unknown. Using a combination of in vitro and in vivo techniques, we now find that RocA interacts with CsrS in the streptococcal membrane via its N-terminal region, which contains seven transmembrane domains. This interaction is essential for RocA-mediated regulation of CsrRS function. Furthermore, we demonstrate that RocA forms homodimers via its cytoplasmic domain. The serotype-specific RocA truncation in M3 isolates alters this homotypic interaction, resulting in protein aggregation and impairment of RocA-mediated regulation. Taken together, our findings provide insight into the molecular requirements for functional interaction of RocA with CsrS to modulate CsrRS-mediated gene regulation. IMPORTANCE Bacterial two-component regulatory systems, comprising a membrane-bound sensor kinase and cytosolic response regulator, are critical in coordinating the bacterial response to changing environmental conditions. More recently, auxiliary regulators which act to modulate the activity of two-component systems, allowing integration of multiple signals and fine-tuning of bacterial responses, have been identified. RocA is a regulatory protein encoded by all serotypes of the important human pathogen group A Streptococcus. Although RocA is known to exert its regulatory activity via the streptococcal two-component regulatory system CsrRS, the mechanism by which it functions was unknown. Based on new experimental evidence, we propose a model whereby RocA interacts with CsrS in the streptococcal cell membrane to enhance CsrS autokinase activity and subsequent phosphotransfer to the response regulator CsrR, which mediates transcriptional repression of target genes.

scholarly journals Structural Basis of the Metal Specificity for Nickel Regulatory Protein NikR†,‡

Biochemistry ◽  
2008 ◽  
Vol 47 (7) ◽  
pp. 1938-1946 ◽  
Author(s):  
Christine M. Phillips ◽  
Eric R. Schreiter ◽  
Yayi Guo ◽  
Sheila C. Wang ◽  
Deborah B. Zamble ◽  
...  
Keyword(s):  
Regulatory Protein ◽  
Structural Basis ◽  
Metal Specificity

scholarly journals Parameters Affecting Continuous In Vitro Culture of Treponema pallidum Strains

mBio ◽  
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Diane G. Edmondson ◽  
Bridget D. DeLay ◽  
Lindsay E. Kowis ◽  
Steven J. Norris
Keyword(s):  
Culture System ◽  
Treponema Pallidum ◽  
Basal Medium ◽  
Human Pathogen ◽  
Low Oxygen ◽  
Term Survival ◽  
Content Type ◽  
Long Term Culture

ABSTRACT The bacterium that causes syphilis, Treponema pallidum subsp. pallidum, has now been cultured in vitro continuously for periods exceeding 3 years using a system consisting of coculture with Sf1Ep rabbit epithelial cells in TpCM-2 medium and a low-oxygen environment. In addition, long-term culture of several other syphilis isolates (SS14, Mexico A, UW231B, and UW249B) and the T. pallidum subsp. endemicum Bosnia A strain has been achieved. During in vitro passage, T. pallidum subsp. pallidum exhibited a typical bacterial growth curve with logarithmic and stationary phases. Sf1Ep cells are required for sustained growth and motility; however, high initial Sf1Ep cell numbers resulted in reduced multiplication and survival. Use of Eagle’s minimal essential medium as the basal medium was not effective in sustaining growth of T. pallidum subsp. pallidum beyond the first passage, whereas CMRL 1066 or M199 supported long-term culture, confirming that additional nutrients present in these more complex basal media are required for long-term culture. T. pallidum subsp. pallidum growth was dependent upon the presence of fetal bovine serum, with 20% (vol/vol) being the optimal concentration. Omission of reactive oxygen species scavengers dithiothreitol, d-mannitol, or l-histidine did not dramatically affect survival or growth. Additionally, T. pallidum subsp. pallidum can be successfully cultured in a Brewer jar instead of a specialized low-oxygen incubator. Phosphomycin or amphotericin B can be added to the medium to aid in the prevention of bacterial or fungal contamination, respectively. These results help define the parameters of the T. pallidum subsp. pallidum culture system that are required for sustained, long-term survival and multiplication. IMPORTANCE Syphilis is caused by the bacterium Treponema pallidum subsp. pallidum. Until recently, this pathogen could only be maintained through infection of rabbits or other animals, making study of this important human pathogen challenging and costly. T. pallidum subsp. pallidum has now been successfully cultured for over 3 years in a tissue culture system using a medium called TpCM-2. Here, we further define the growth requirements of this important human pathogen, promoting a better understanding of the biology of this fastidious organism.

scholarly journals The Helicobacter pylori Homologue of the Ferric Uptake Regulator Is Involved in Acid Resistance

2002 ◽  
Vol 70 (2) ◽  
pp. 606-611 ◽  
Author(s):  
Jetta J. E. Bijlsma ◽  
Barbara Waidner ◽  
Arnoud H. M. van Vliet ◽  
Nicky J. Hughes ◽  
Stephanie Häg ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Iron Homeostasis ◽  
Regulatory Protein ◽  
Acid Resistance ◽  
Low Ph ◽  
Main Function ◽  
Ferric Uptake Regulator ◽  
Acidic Ph ◽  
Human Pathogen ◽  
H Pylori

ABSTRACT The only known niche of the human pathogen Helicobacter pylori is the gastric mucosa, where large fluctuations of pH occur, indicating that the bacterial response and resistance to acid are important for successful colonization. One of the few regulatory proteins in the H. pylori genome is a homologue of the ferric uptake regulator (Fur). In most bacteria, the main function of Fur is the regulation of iron homeostasis. However, in Salmonella enterica serovar Typhimurium, Fur also plays an important role in acid resistance. In this study, we determined the role of the H. pylori Fur homologue in acid resistance. Isogenic fur mutants were generated in three H. pylori strains (1061, 26695, and NCTC 11638). At pH 7 there was no difference between the growth rates of mutants and the parent strains. Under acidic conditions, growth of the fur mutants was severely impaired. No differences were observed between the survival of the fur mutant and parent strain 1061 after acid shock. Addition of extra iron or removal of iron from the growth medium did not improve the growth of the fur mutant at acidic pH. This indicates that the phenotype of the fur mutant at low pH was not due to increased iron sensitivity. Transcription of fur was repressed in response to low pH. From this we conclude that Fur is involved in the growth at acidic pH of H. pylori; as such, it is the first regulatory protein implicated in the acid resistance of this important human pathogen.

scholarly journals Purification, crystallization and preliminary X-ray analysis of TP0435 (Tp17) from the syphilis spirocheteTreponema pallidum

2013 ◽  
Vol 69 (4) ◽  
pp. 453-455 ◽  
Author(s):  
Chad A. Brautigam ◽  
Ranjit K. Deka ◽  
Michael V. Norgard
Keyword(s):  
Structural Biology ◽  
Treponema Pallidum ◽  
Gene Products ◽  
Human Pathogen ◽  
Unit Cell Parameters ◽  
Transmitted Infection ◽  
X Ray ◽  
Sexually Transmitted ◽  
Cell Parameters ◽  
Apparent Homogeneity

Syphilis, caused by the bacterial spirocheteTreponema pallidum, remains a prominent sexually transmitted infection worldwide. Despite sequencing of the genome of this obligate human pathogen 15 years ago, the functions of a large number of the gene products ofT. pallidumare still unknown, particularly with respect to those of the organism's periplasmic lipoproteins. To better understand their functions, a structural biology approach has been pursued. To this end, the soluble portion of theT. pallidumTP0435 lipoprotein (also known as Tp17) was cloned, hyper-expressed inEscherichia coliand purified to apparent homogeneity. The protein crystals obtained from this preparation diffracted to 2.4 Å resolution and had the symmetry of space groupR3. In the hexagonal setting, the unit-cell parameters werea=b= 85.7,c= 85.4 Å.

scholarly journals Phenotypes Associated with the Essential Diadenylate Cyclase CdaA and Its Potential Regulator CdaR in the Human Pathogen Listeria monocytogenes

2015 ◽  
Vol 198 (3) ◽  
pp. 416-426 ◽  
Author(s):  
Jeanine Rismondo ◽  
Johannes Gibhardt ◽  
Jonathan Rosenberg ◽  
Volkhard Kaever ◽  
Sven Halbedel ◽  
...  
Keyword(s):  
Cell Division ◽  
Listeria Monocytogenes ◽  
Membrane Protein ◽  
Regulatory Protein ◽  
Second Messenger ◽  
Integral Membrane Protein ◽  
Membrane Localization ◽  
Human Pathogen ◽  
Content Type ◽  
The Relationship

ABSTRACTCyclic diadenylate monophosphate (c-di-AMP) is a second messenger utilized by diverse bacteria. In many species, including the Gram-positive human pathogenListeria monocytogenes, c-di-AMP is essential for growth. Here we show that the single diadenylate cyclase ofL. monocytogenes, CdaA, is an integral membrane protein that interacts with its potential regulatory protein, CdaR, via the transmembrane protein domain. The presence of the CdaR protein is not required for the membrane localization and abundance of CdaA. We have also found that CdaR negatively influences CdaA activity inL. monocytogenesand that the role of CdaR is most evident at a high growth temperature. Interestingly, acdaRmutant strain is less susceptible to lysozyme. Moreover, CdaA contributes to cell division, and cells depleted of CdaA are prone to lysis. The observation that the growth defect of a CdaA depletion strain can be partially restored by increasing the osmolarity of the growth medium suggests that c-di-AMP is important for maintaining the integrity of the protective cell envelope. Overall, this work provides new insights into the relationship between CdaA and CdaR.IMPORTANCECyclic diadenylate monophosphate (c-di-AMP) is a recently identified second messenger that is utilized by the Gram-positive human pathogenListeria monocytogenes. Here we show that the single diadenylate cyclase ofL. monocytogenes, CdaA, is an integral membrane protein that interacts with CdaR, its potential regulatory protein. We show that CdaR is not required for membrane localization or abundance of the diadenylate cyclase, but modulates its activity. Moreover, CdaA seems to contribute to cell division. Overall, this work provides new insights into the relationship between CdaA and CdaR and their involvement in cell growth.

scholarly journals Characterization of a manganese-dependent regulatory protein, TroR, from Treponema pallidum

1999 ◽  
Vol 96 (19) ◽  
pp. 10887-10892 ◽  
Author(s):  
J. E. Posey ◽  
J. M. Hardham ◽  
S. J. Norris ◽  
F. C. Gherardini
Keyword(s):  
Regulatory Protein ◽  
Treponema Pallidum

Probing the metal specificity mechanism of superoxide dismutase from human pathogen Clostridium difficile

2014 ◽  
Vol 50 (5) ◽  
pp. 584-586 ◽  
Author(s):  
Wei Li ◽  
Hongfei Wang ◽  
Zheng Chen ◽  
Qing Ye ◽  
Yang Tian ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Clostridium Difficile ◽  
Human Pathogen ◽  
Metal Specificity

scholarly journals The Response of Acinetobacter baumannii to Hydrogen Sulfide Reveals Two Independent Persulfide-Sensing Systems and a Connection to Biofilm Regulation

mBio ◽  
2020 ◽  
Vol 11 (3) ◽  
Author(s):  
Brenna J. C. Walsh ◽  
Jiefei Wang ◽  
Katherine A. Edmonds ◽  
Lauren D. Palmer ◽  
Yixiang Zhang ◽  
...  
Keyword(s):  
Hydrogen Sulfide ◽  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Sulfide Oxidation ◽  
Regulatory Protein ◽  
Transcriptional Regulators ◽  
Human Pathogen ◽  
Secondary System ◽  
Biofilm Growth ◽  
Content Type

ABSTRACT Acinetobacter baumannii is an opportunistic nosocomial pathogen that is the causative agent of several serious infections in humans, including pneumonia, sepsis, and wound and burn infections. A. baumannii is also capable of forming proteinaceous biofilms on both abiotic and epithelial cell surfaces. Here, we investigate the response of A. baumannii toward sodium sulfide (Na2S), known to be associated with some biofilms at oxic/anoxic interfaces. The addition of exogenous inorganic sulfide reveals that A. baumannii encodes two persulfide-sensing transcriptional regulators, a primary σ54-dependent transcriptional activator (FisR), and a secondary system controlled by the persulfide-sensing biofilm growth-associated repressor (BigR), which is only induced by sulfide in a fisR deletion strain. FisR activates an operon encoding a sulfide oxidation/detoxification system similar to that characterized previously in Staphylococcus aureus, while BigR regulates a secondary persulfide dioxygenase (PDO2) as part of yeeE-yedE-pdo2 sulfur detoxification operon, found previously in Serratia spp. Global S-sulfuration (persulfidation) mapping of the soluble proteome reveals 513 persulfidation targets well beyond FisR-regulated genes and includes five transcriptional regulators, most notably the master biofilm regulator BfmR and a poorly characterized catabolite regulatory protein (Crp). Both BfmR and Crp are well known to impact biofilm formation in A. baumannii and other organisms, respectively, suggesting that persulfidation of these regulators may control their activities. The implications of these findings on bacterial sulfide homeostasis, persulfide signaling, and biofilm formation are discussed. IMPORTANCE Although hydrogen sulfide (H2S) has long been known as a respiratory poison, recent reports in numerous bacterial pathogens reveal that H2S and more downstream oxidized forms of sulfur collectedly termed reactive sulfur species (RSS) function as antioxidants to combat host efforts to clear the infection. Here, we present a comprehensive analysis of the transcriptional and proteomic response of A. baumannii to exogenous sulfide as a model for how this important human pathogen manages sulfide/RSS homeostasis. We show that A. baumannii is unique in that it encodes two independent persulfide sensing and detoxification pathways that govern the speciation of bioactive sulfur in cells. The secondary persulfide sensor, BigR, impacts the expression of biofilm-associated genes; in addition, we identify two other transcriptional regulators known or projected to regulate biofilm formation, BfmR and Crp, as highly persulfidated in sulfide-exposed cells. These findings significantly strengthen the connection between sulfide homeostasis and biofilm formation in an important human pathogen.

Von Hermaphroditos der griechischen Mythologie bis zu DSD der Moderne

Praxis ◽  
2008 ◽  
Vol 98 (1) ◽  
pp. 31-34
Author(s):  
Oestmann ◽  
Mullis ◽  
Stanga
Keyword(s):  
Regulatory Protein ◽  
Steroidogenic Acute Regulatory Protein ◽  
Sich Eine ◽  
Fand Sich ◽  
Steroidogenic Acute Regulatory

Wir berichten über eine heute 34-jährige Frau, die im Alter von 6 Monaten wegen rezidivierendem Erbrechen hospitalisiert werden musste. Als Ursache fand sich eine Nebenniereninsuffizienz mit Verminderung sämtlicher Hormone der Steroidhormonbiosynthese. Die weiteren Abklärungen ergaben bei dem phänotypisch weiblichen Säugling eine lipoide kongenitale adrenale Hyperplasie mit 46,XY DSD. 24 Jahre später konnte in der DNS-Sequenzanalyse ein homozygoter, in der Schweiz vorkommender Basenaustausch des steroidogenic acute regulatory protein-Gens gefunden werden, welcher zu einem Aminosäurenaustausch Leucin 260 Prolin (L260P) führt.

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