Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.2.2.10 (PNL)
 341 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activation of pectin lyase (Pnl) production in Erwinia carotovora subsp. carotovora strain 71 occurs upon DNA damage via a unique regulatory circuit involving recA, rdgA and rdgB. In a similar Pnl-inducible system reconstituted in Escherichia coli, the rdgB product was found to activate the expression of pnlA, the structural gene for pectin lyase. The kinetic data presented here also show that transcription of pnlA followed that of rdgB in Er. carotovora subsp. carotovora, indicating a temporal order of gene expression. By deletion analysis we have localized the promoter/regulatory region within a 66 bp DNA segment upstream of the pnlA transcriptional start site. This region contains the -10 consensus sequence but not the sequences corresponding to the E. coli -35 region. For DNA-binding studies, rdgB was overexpressed in E. coli and a 14 kDa polypeptide was identified as the gene product. RdgB from crude extracts or a purified preparation caused an identical gel mobility shift of a 164 bp DNA segment containing the pnlA promoter/regulatory region. Utilizing DNase I protection assay the RdgB-binding site was localized between nucleotides -29 and -56, i.e. overlapping the position of the putative -35 box. The findings reported here, taken along with our previous observation that the rdgE product is required for pnlA expression, establishes that rdgB encodes a transcriptional factor which specifically interacts with the pnlA promoter/regulatory region.
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PMID:Activation of the Erwinia carotovora subsp. carotovora pectin lyase structural gene pnlA: a role for RdgB. 908 57

The CT1 mutant of Penicillium occitanis hyperproduces extracellular pectinases constitutively since it secretes pectinases even on glucose-containing medium. We show here that all other hydrolytic enzymes remain at low activities in CT1, confirming the specificity of the regulatory mutation towards pectinases. We isolated, by RT-PCR and through the construction of a cDNA library, three fragments coding for: a pectin lyase (pnl1), a polygalacturonase (pga1) and a pectate lyase (pal1). These fragments were used as probes in Northern blots analysis of the wild type strain CL100 and the CT1 mutant of P. occitanis grown in three culture conditions. The CT1 mutant showed a very high amount of pnl1, pga1 and pal1 mRNA either in pectin, glucose or glycerol grown cells while in the wild type CL100 strain, all transcripts were undetectable even on pectin. These results suggest that the CT1 mutation affects a trans-regulatory transcriptional factor regulating pectinase expression.
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PMID:Constitutive over-expression of pectinases in Penicillium occitanis CT1 mutant is transcriptionally regulated. 2128 29