scholarly journals Cotranslational translocation and folding of a periplasmic protein domain in Escherichia coli

2021 ◽  
pp. 167047
Author(s):  
Hena Sandhu ◽  
Rickard Hedman ◽  
Florian Cymer ◽  
Renuka Kudva ◽  
Nurzian Ismail ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Protein Domain ◽  
Periplasmic Protein ◽  
Cotranslational Translocation

scholarly journals CpxP, a Stress-Combative Member of the Cpx Regulon

1998 ◽  
Vol 180 (4) ◽  
pp. 831-839 ◽  
Author(s):  
Paul N. Danese ◽  
Thomas J. Silhavy
Keyword(s):  
Escherichia Coli ◽  
Envelope Protein ◽  
Periplasmic Protein ◽  
Dependent Manner ◽  
Alkaline Ph ◽  
Signal Transduction System ◽  
Two Component ◽  
Mutant Strains ◽  
Alkaline Conditions ◽  
Two Component Signal Transduction

ABSTRACT The CpxA/R two-component signal transduction system ofEscherichia coli can combat a variety of extracytoplasmic protein-mediated toxicities. The Cpx system performs this function, in part, by increasing the synthesis of the periplasmic protease, DegP. However, other factors are also employed by the Cpx system for this stress-combative function. In an effort to identify these remaining factors, we screened a collection of random lacZ operon fusions for those fusions whose transcription is regulated by CpxA/R. Through this approach, we have identified a new locus,cpxP, whose transcription is stimulated by activation of the Cpx pathway. cpxP specifies a periplasmic protein that can combat the lethal phenotype associated with the synthesis of a toxic envelope protein. In addition, we show that cpxPtranscription is strongly induced by alkaline pH in a CpxA-dependent manner and that cpxP and cpx mutant strains display hypersensitivity to growth in alkaline conditions.

scholarly journals Role of the PDZ Domains in Escherichia coli DegP Protein

2007 ◽  
Vol 189 (8) ◽  
pp. 3176-3186 ◽  
Author(s):  
Jack Iwanczyk ◽  
Daniela Damjanovic ◽  
Joel Kooistra ◽  
Vivian Leong ◽  
Ahmad Jomaa ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Protease Activity ◽  
Pdz Domain ◽  
Structural Features ◽  
Periplasmic Protein ◽  
Pdz Domains ◽  
Protease Domain ◽  
Interaction Domains ◽  
And Function

ABSTRACT PDZ domains are modular protein interaction domains that are present in metazoans and bacteria. These domains possess unique structural features that allow them to interact with the C-terminal residues of their ligands. The Escherichia coli essential periplasmic protein DegP contains two PDZ domains attached to the C-terminal end of the protease domain. In this study we examined the role of each PDZ domain in the protease and chaperone activities of this protein. Specifically, DegP mutants with either one or both PDZ domains deleted were generated and tested to determine their protease and chaperone activities, as well as their abilities to sequester unfolded substrates. We found that the PDZ domains in DegP have different roles; the PDZ1 domain is essential for protease activity and is responsible for recognizing and sequestering unfolded substrates through C-terminal tags, whereas the PDZ2 domain is mostly involved in maintaining the hexameric cage of DegP. Interestingly, neither of the PDZ domains was required for the chaperone activity of DegP. In addition, we found that the loops connecting the protease domain to PDZ1 and connecting PDZ1 to PDZ2 are also essential for the protease activity of the hexameric DegP protein. New insights into the roles of the PDZ domains in the structure and function of DegP are provided. These results imply that DegP recognizes substrate molecules targeted for degradation and substrate molecules targeted for refolding in different manners and suggest that the substrate recognition mechanisms may play a role in the protease-chaperone switch, dictating whether the substrate is degraded or refolded.

Novel insights into the metal binding ability of ZinT periplasmic protein from Escherichia coli and Salmonella enterica

2020 ◽  
Vol 49 (27) ◽  
pp. 9393-9403
Author(s):  
Denise Bellotti ◽  
Magdalena Rowińska-Żyrek ◽  
Maurizio Remelli
Keyword(s):  
Escherichia Coli ◽  
Metal Binding ◽  
Salmonella Enterica ◽  
Periplasmic Protein ◽  
Binding Ability ◽  
Primary Metal ◽  
Metal Binding Ability

The characterization of Zn(ii) and Cu(ii) complexes with periplasmic protein ZinT suggests that the N-terminal histidine-rich loop plays a role as a primary metal scavenger and that ZinT can possibly transfer a Zn(ii) ion to ZnuA.

Sign in / Sign up

Export Citation Format

Share Document