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)

A collection of 54 clinical and agricultural isolates of Burkholderia cenocepacia was analyzed for genetic relatedness by using multilocus sequence typing (MLST), pathogenicity by using onion and nematode infection models, antifungal activity, and the distribution of three marker genes associated with virulence. The majority of clinical isolates were obtained from cystic fibrosis (CF) patients in Michigan, and the agricultural isolates were predominantly from Michigan onion fields. MLST analysis resolved 23 distinct sequence types (STs), 11 of which were novel. Twenty-six of 27 clinical isolates from Michigan were genotyped as ST-40, previously identified as the Midwest B. cenocepacia lineage. In contrast, the 12 agricultural isolates represented eight STs, including ST-122, that were identical to clinical isolates of the PHDC lineage. In general, pathogenicity to onions and the presence of the pehA endopolygalacturonase gene were detected only in one cluster of related strains consisting of agricultural isolates and the PHDC lineage. Surprisingly, these strains were highly pathogenic in the nematode Caenorhabditis elegans infection model, killing nematodes faster than the CF pathogen Pseudomonas aeruginosa PA14 on slow-kill medium. The other strains displayed a wide range of pathogenicity to C. elegans, notably the Midwest clonal lineage which displayed high, moderate, and low virulence. Most strains displayed moderate antifungal activity, although strains with high and low activities were also detected. We conclude that pathogenicity to multiple hosts may be a key factor contributing to the potential of B. cenocepacia to opportunistically infect humans both by increasing the prevalence of the organism in the environment, thereby increasing exposure to vulnerable hosts, and by the selection of virulence factors that function in multiple hosts.
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PMID:Genetic diversity and multihost pathogenicity of clinical and environmental strains of Burkholderia cenocepacia. 1954 23

Burkholderia cenocepacia AU1054 is an opportunistic pathogen isolated from the blood of a person with cystic fibrosis. AU1054 is a multihost pathogen causing rapid pathogenicity to Caenorhabditis elegans nematodes. Within 24 h, AU1054 causes greater than 50% mortality, reduced growth, emaciated body, distended intestinal lumen, rectal swelling, and prolific infection of the nematode intestine. To determine virulence mechanisms, 3,000 transposon mutants were screened for attenuated virulence in nematodes. Fourteen virulence-attenuated mutants were isolated, and the mutant genes were identified. These genes included paaA, previously identified as being required for full virulence of B. cenocepacia K56-2. Six mutants were restored in virulence by complementation with their respective wild-type gene. One of these contained an insertion in gspJ, predicted to encode a pseudopilin component of the type 2 secretion system (T2SS). Nematodes infected with AU1054 gspJ had fewer bacteria present in the intestine than those infected with the wild type but still showed rectal swelling. The gspJ mutant was also defective in pathogenicity to onion and in degradation of polygalacturonic acid and casein. This result differs from previous studies where no or little role was found for T2SS in Burkholderia virulence, although virulence factors such as zinc metalloproteases and polygalacturonase are known to be secreted by the T2SS. This study highlights strain specific differences in B. cenocepacia virulence mechanisms important for understanding what enables environmental microbes to function as opportunistic pathogens.
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PMID:The type 2 secretion Pseudopilin, gspJ, is required for multihost pathogenicity of Burkholderia cenocepacia AU1054. 2066 Jun 7