Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.15 (pectinase)
 2,440 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Erwinia chrysanthemi is an enterobacterium that causes various plant diseases. Its pathogenicity results from the secretion of pectinolytic enzymes responsible for the disorganization of the plant cell wall. The E. chrysanthemi strain 3937 produces two pectin methylesterases, at least seven pectate lyases, a polygalacturonase, and a pectin lyase. The extracellular degradation of the pectin leads to the formation of oligogalacturonides that are catabolized through an intracellular pathway. The pectinase genes are expressed from independent cistrons, and their transcription is favored by environmental conditions such as presence of pectin and plant extracts, stationary growth phase, low temperature, oxygen or iron limitation, and so on. Moreover, transcription of the pectin lyase gene responds to DNA-damaging agents. The differential expressions of individual pectinase genes presumably reflect their role during plant infection. The regulation of pel genes requires several regulatory systems, including the KdgR repressor, which mediates the induction of all the pectinolysis genes in the presence of pectin catabolites. KdgR also controls the genes necessary for pectinase secretion and other pectin-inducible genes not yet characterized. PecS, a cytoplasmic protein homologous to other transcriptional regulators, can bind in vitro to the regulatory regions of pectinase and cellulase genes. The PecT protein, a member of the LysR family of transcriptional regulators, represses the expression of some pectinase genes and also affects other metabolic pathways of the bacteria. Other proteins involved in global regulations, such as CRP or HNS, can bind to the regulatory regions of the pectinase genes and affect their transcription.
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PMID:Regulation of pectinolysis in Erwinia chrysanthemi. 890 80

The plant-pathogenic bacterium Dickeya dadantii (formerly Erwinia chrysanthemi) produces a large array of plant cell wall-degrading enzymes. Using an in situ detection test, we showed that it produces two feruloyl esterases, FaeD and FaeT. These enzymes cleave the ester link between ferulate and the pectic or xylan chains. FaeD and FaeT belong to the carbohydrate esterase family CE10, and they are the first two feruloyl esterases to be identified in this family. Cleavage of synthetic substrates revealed strong activation of FaeD and FaeT by ferulic acid. The gene faeT appeared to be weakly expressed, and its product, FaeT, is a cytoplasmic protein. In contrast, the gene faeD is strongly induced in the presence of ferulic acid, and FaeD is an extracellular protein secreted by the Out system, responsible for pectinase secretion. The product of the adjacent gene faeR is involved in the positive control of faeD in response to ferulic acid. Moreover, ferulic acid acts in synergy with polygalacturonate to induce pectate lyases, the main virulence determinant of soft rot disease. Feruloyl esterases dissociate internal cross-links in the polysaccharide network of the plant cell wall, suppress the polysaccharide esterifications, and liberate ferulic acid, which contributes to the induction of pectate lyases. Together, these effects of feruloyl esterases could facilitate soft rot disease caused by pectinolytic bacteria.
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PMID:Identification of two feruloyl esterases in Dickeya dadantii 3937 and induction of the major feruloyl esterase and of pectate lyases by ferulic acid. 2116 94