semiotic examination and stylistics in both phonetic level and syntactic level of sura nouh            danesh mohammadi rakati *   alireza mohammad rezaei **      abstract      stylistic is one of the important methods in linguistics, that many of the linguistic researches about quran are based on it. this article seeks to use statistical methods to explore the implications of language in sura ...

UNLABELLED SurA is a component of the periplasmic chaperone network that plays a central role in biogenesis of integral outer membrane β-barrel proteins (OMPs) in Escherichia coli. Although SurA contains two well-conserved proline isomerase (PPIase) domains, the contribution of these domains to SurA function is unclear. In the present work, we show that defects in OMP assembly caused by mutatio...

The periplasm of Escherichia coli contains many proteins proposed to have redundant functions in protein folding. Using depletion analysis, we directly demonstrated that null mutations in skp and surA, as well as in degP and surA, result in synthetic phenotypes, suggesting that Skp, SurA, and DegP are functionally redundant. The Deltaskp surA::kan combination has a bacteriostatic effect and lea...

SurA is the primary periplasmic molecular chaperone that facilitates the folding and assembling of outer membrane proteins (OMPs) in Gram-negative bacteria. Deletion of the surA gene in Escherichia coli leads to a decrease in outer membrane density and an increase in bacterial drug susceptibility. Here, we conducted mutational studies on SurA to identify residues that are critical for function....

UNLABELLED The periplasmic chaperone SurA is critical for the biogenesis of outer membrane proteins (OMPs) and, thus, the maintenance of membrane integrity in Escherichia coli. The activity of this modular chaperone has been attributed to a core chaperone module, with only minor importance assigned to the two SurA peptidyl-prolyl isomerase (PPIase) domains. In this work, we used synthetic pheno...

Escherichia coli is the most common cause of community-acquired urinary tract infection (UTI). During murine cystitis, uropathogenic E. coli (UPEC) utilizes type 1 pili to bind and invade superficial bladder epithelial cells. UPEC then replicates within to form intracellular bacterial communities (IBCs), a process whose genetic determinants are as yet undefined. In this study, we investigated t...

SurA is a major periplasmic molecular chaperone in Escherichia coli and has been shown to assist the biogenesis of several outer membrane proteins. The C-terminal fragment of SurA folds into a short β-strand, which forms a small three-stranded anti-parallel β-sheet module with the N-terminal β-hairpin. We found that the length of the C-terminal fragment, rather than its exact amino acid composi...

BACKGROUND SurA is a periplasmic peptidyl-prolyl isomerase (PPIase) and chaperone of Escherichia coli and other Gram-negative bacteria. In contrast to other PPIases, SurA appears to have a distinct role in chaperoning newly synthesized porins destined for insertion into the outer membrane. Previous studies have indicated that the chaperone activity of SurA rests in its "core module" (the N- plu...

Integral beta-barrel proteins (OMPs) are a major class of outer membrane proteins in Gram-negative bacteria. In Escherichia coli, these proteins are synthesized in the cytoplasm, translocated across the inner membrane via the Sec machinery, and assembled in the outer membrane through an unknown mechanism that requires the outer membrane YaeT complex and the periplasmic chaperones SurA, DegP, an...

Periplasmic PPIases (peptidylprolyl cis-trans isomerases) catalyse the cis-trans isomerization of peptidyl-prolyl bonds, which is a rate-limiting step during protein folding. We demonstrate that the surA, ppiA, ppiD, fkpA and fklB alleles each encode a periplasmic PPIase in the bacterial pathogen Yersinia pseudotuberculosis. Of these, four were purified to homogeneity. Purified SurA, FkpA and F...