OL-024 vfr: A novel locus affecting cysteine protease production in Streptococcus pyogenes

Activation of a 66-kilodalton human endothelial cell matrix metalloprotease by Streptococcus pyogenes extracellular cysteine protease.

Human umbilical vein endothelial cells (HUVECs) were used to gain insight into the molecular mechanism whereby the major extracellular protease from group A streptococci damages host tissue. HUVECs exposed to streptococcal cysteine protease (SCP) for various times exhibited cytopathic effect and cell detachment from the culture vessel. Gelatin substrate zymography showed that a time- and concen...

Role of RopB in growth phase expression of the SpeB cysteine protease of Streptococcus pyogenes.

The Rgg family of transcription regulators is widely distributed among gram-positive bacteria; however, how the members of this family control transcription is poorly understood. In the pathogen Streptococcus pyogenes, the Rgg family member RopB is required for transcription of the gene that encodes the secreted SpeB cysteine protease. Expression of the protease follows distinct kinetics that i...

Streptococcus pyogenes of the SpeB Cysteine Protease of Role of RopB in Growth Phase Expression

Trigger factor-mediated prolyl isomerization influences maturation of the Streptococcus pyogenes cysteine protease.

Trigger factor, a ribosome-associated chaperone and peptidyl-prolyl cis-trans isomerase (PPIase), is essential for the secretion and maturation of the cysteine protease of the pathogenic gram-positive bacterium Streptococcus pyogenes. In the absence of trigger factor, the nascent protease polypeptide is not targeted to the secretory pathway. Some partial-function mutations restore targeting. Ho...

Novel Regulatory Small RNAs in Streptococcus pyogenes

Streptococcus pyogenes (Group A Streptococcus or GAS) is a Gram-positive bacterial pathogen that has shown complex modes of regulation of its virulence factors to cause diverse diseases. Bacterial small RNAs are regarded as novel widespread regulators of gene expression in response to environmental signals. Recent studies have revealed that several small RNAs (sRNAs) have an important role in S...