Conserved DegP Protease in Gram-Positive Bacteria Is Essential for Thermal and Oxidative Tolerance and Full Virulence in
            <i>Streptococcus pyogenes</i>

Jones, C. Hal; Bolken, Tove’ C.; Jones, Kevin F.; Zeller, Gloria O.; Hruby, Dennis E.

doi:10.1128/iai.69.9.5538-5545.2001

Cited by 73 publications

(85 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Deletion of htrA in S. pneumoniae significantly reduced nasopharyngeal colonization (486) and virulence in mouse models of pneumonia and bacteremia (487,488). The 50% lethal dose (LD 50 ) for an S. pyogenes htrA mutant in mice was 35-fold higher than that for the parent strain (489). A subsequent study revealed that HtrA is responsible for processing secreted virulence factors, such as the SpeB cysteine protease and streptolysin S (490).…”

Section: General Stress Responses and Virulencementioning

confidence: 99%

Stress Physiology of Lactic Acid Bacteria

Papadimitriou

Alegría

Bron

et al. 2016

Microbiol Mol Biol Rev

541

404

View full text Add to dashboard Cite

SUMMARYLactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g.,Lactococcus lactis), probiotic (e.g., severalLactobacillusspp.), and pathogenic (e.g.,EnterococcusandStreptococcusspp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the “stressome” of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance.

show abstract

Section: General Stress Responses and Virulencementioning

confidence: 99%

Stress Physiology of Lactic Acid Bacteria

Papadimitriou

Alegría

Bron

et al. 2016

Microbiol Mol Biol Rev

541

404

View full text Add to dashboard Cite

show abstract

“…Bacterial HtrA proteins perform several functions, which include non-destructive protein processing (Carvard et al, 1989), modulation of signaling pathways mediated by the elimination of regulatory proteins (Alba et al, 2001), resistance to heat stress (Lipinska et al, 1988;Li et al, 1996;Poquet et al, 2000;Wonderling et al, 2004) and virulence (Baumler et al, 1994;Elzer et al, 1996.;Jones et al, 2001;Yorgey et al, 2001).…”

Section: Function Of Degpqsmentioning

confidence: 99%

Structure and Function of HtrA Family Proteins, the Key Players in Protein Quality Control

Kim¹,

Kim²

2005

BMB Reports

130

159

View full text Add to dashboard Cite

High temperature requirement A (HtrA) and its homologues constitute the HtrA familiy proteins, a group of heat shock-induced serine proteases. Bacterial HtrA proteins perform crucial functions with regard to protein quality control in the periplasmic space, functioning as both molecular chaperones and proteases. In contrast to other bacterial quality control proteins, including ClpXP, ClpAP, and HslUV, HtrA proteins contain no regulatory components or ATP binding domains. Thus, they are commonly referred to as ATP-independent chaperoneproteases. Whereas the function of ATP-dependent chaperone-proteases is regulated by ATP hydrolysis, HtrA exhibits a PDZ domain and a temperature-dependent switch mechanism, which effects the change in its function from molecular chaperone to protease. This mechanism is also related to substrate recognition and the fine control of its function. Structural and biochemical analyses of the three HtrA proteins, DegP, DegQ, and DegS, have provided us with clues as to the functional regulation of HtrA proteins, as well as their roles in protein quality control at atomic scales. The objective of this brief review is to discuss some of the recent studies which have been conducted regarding the structure and function of these HtrA proteins, and to compare their roles in the context of protein quality control.

show abstract

“…This is not the case in Salmonella, but S. Typhimurium htrA mutants exhibit increased sensitivity to killing by reactive oxygen species and reduced survival and/or replication within macrophages (Baumler et al, 1994;Humphreys et al, 1999;Johnson et al, 1991), and are highly attenuated in the murine model of systemic Salmonella infection (Chatfield et al, 1992;Humphreys et al, 1999). Since the seminal studies in Salmonella, HtrA has been found to play a role in the virulence of a wide range of Gram-negative and Grampositive bacterial pathogens (Bringer et al, 2005;Cortes et al, 2002;Humphreys et al, 1999;Ibrahim et al, 2004;Johnson et al, 1991;Jones et al, 2001;Pallen & Wren, 1997;Pedersen et al, 2001;Rigoulay et al, 2005;Williams et al, 2000).…”

Section: Introductionmentioning

confidence: 99%

Salmonella enterica Serovar Typhimurium HtrA: regulation of expression and role of the chaperone and protease activities during infection

Lewis

Škovierová²,

Rowley

et al. 2009

Microbiology

View full text Add to dashboard Cite

HtrA is a bifunctional stress protein required by many bacterial pathogens to successfully cause infection. Salmonella enterica serovar Typhimurium (S. Typhimurium) htrA mutants are defective in intramacrophage survival and are highly attenuated in mice. Transcription of htrA in Escherichia coli is governed by a single promoter that is dependent on s E (RpoE). S. Typhimurium htrA also possesses a s E -dependent promoter; however, we found that the absence of s E had little effect on production of HtrA by S. Typhimurium. This suggests that additional promoters control expression of htrA in S. Typhimurium. We identified three S. Typhimurium htrA promoters. Only the most proximal promoter, htrAp3, was s E dependent. The other promoters, htrAp1 and htrAp2, are probably recognized by the principal sigma factor s 70 . These two promoters were constitutively expressed but were also slightly induced by heat shock. Thus expression of htrA is different in S. Typhimurium and E. coli. The role of HtrA is to deal with misfolded/damaged proteins in the periplasm. It can do this either by degrading (protease activity) or folding/capturing (chaperone/sequestering, C/S, activity) the aberrant protein. We investigated which of these functions are important to S. Typhimurium in vitro and in vivo. Point or deletion mutants of htrA that encode variant HtrA molecules have been used in previous studies to investigate the role of different regions of HtrA in C/S and protease activity. These htrA variants were placed under the control of the S. Typhimurium htrAP123 promoters and expressed in a S. Typhimurium htrA mutant, GVB1343. Both wild-type HtrA and HtrA (HtrA S210A) lacking protease activity enabled GVB1343 to grow at high temperature (46 6C). Both molecules also significantly enhanced the growth/survival of GVB1343 in the liver and spleen of mice during infection. However, expression of wild-type HtrA enabled GVB1343 to grow to much higher levels than expression of HtrA S210A. Thus both the protease and C/S functions of HtrA operate in vivo during infection but the protease function is probably more important. Absence of either PDZ domain completely abolished the ability of HtrA to complement the growth defects of GVB1343 in vitro or in vivo.

show abstract

Conserved DegP Protease in Gram-Positive Bacteria Is Essential for Thermal and Oxidative Tolerance and Full Virulence in Streptococcus pyogenes

Cited by 73 publications

References 47 publications

Stress Physiology of Lactic Acid Bacteria

Stress Physiology of Lactic Acid Bacteria

Structure and Function of HtrA Family Proteins, the Key Players in Protein Quality Control

Salmonella enterica Serovar Typhimurium HtrA: regulation of expression and role of the chaperone and protease activities during infection

Contact Info

Product

Resources

About