Nucleotide sequence of the Escherichia coli cad operon: a system for neutralization of low extracellular pH.

Bennett extracellular pH . cad operon : a system for neutralization of low Nucleotide sequence of the Escherichia

Regulation of the Escherichia coli cad operon: location of a site required for acid induction.

The cad operon encodes lysine decarboxylase and a protein homologous to amino acid antiporters. These two genes are induced under conditions of low pH, anaerobiosis, and excess lysine. The upstream regulatory region of the cad operon has been cloned into lacZ expression vectors for analysis of the sequences involved in these responses. Deletion analysis of the upstream region and cloning of var...

Identification of elements involved in transcriptional regulation of the Escherichia coli cad operon by external pH.

Expression of the lysine decarboxylase gene (cadA) of Escherichia coli is induced upon external acidification. To dissect the molecular mechanisms responsible for this regulation, we analyzed a 4.2-kbp region upstream from cadA. DNA sequencing revealed two long open reading frames upstream of and on the same strand as cadA. One of these, cadB, is 444 codons long and is situated immediately upst...

Antifungal Activity of Heterologous Expressed Chitinase 42 (Chit42) from Trichoderma atroviride PTCC5220

The cDNA from the mycoparasitic fungus Trichoderma atroviride PTCC5220 encoding a 42 kDa chitinase (Chit42) was isolated. The nucleotide sequence of the cDNA fragment as having a 1263 bp open reading frame that encodes a 421 amino acid polypeptide, and a high homology was found withother reported Chit42 belonging to the Trichoderma sp. The 22 amino acid N-terminal sequence is a putative s...

Two copies of Shiga-like toxin II-related genes common in enterohemorrhagic Escherichia coli strains are responsible for the antigenic heterogeneity of the O157:H- strain E32511.

Thirty-two clinical isolates of Shiga-like toxin (SLT)-producing Escherichia coli associated with single cases or outbreaks of bloody diarrhea, hemorrhagic colitis, the hemolytic uremic syndrome, or edema disease of swine were examined for multiple copies of genes belonging to the slt-I or slt-II toxin families. Five of 19 strains that were known to produce SLT-II or to hybridize to slt-II-spec...