Sequence analysis of the chitin synthase A gene of the Dutch elm pathogen Ophiostoma novo-ulmi indicates a close association with the human pathogen Sporothrix schenckii.
Degenerate oligonucleotide primers were designed according to conserved regions of the chitin synthase gene family and used to amplify a 621 basepair (bp) fragment from genomic DNA of Ophiostoma novo-ulmi, the causal agent of Dutch elm disease. The amplification product was used as a hybridization probe to screen a library of genomic DNA sequences and to retrieve a full-length chitin synthase gene (chsA). The putative coding region of the gene was 2619 bp long, lacked introns, and encoded a polypeptide of 873 amino acids. Based on the similarity of the predicted amino acid sequence to the full-length chsC gene of Aspergillus nidulans and chsA gene of Ampelomyces quisqualis, the O. novo-ulmi chsA was classified as a Class I chitin synthase. The phylogenies constructed, according to a subregion of all available chitin synthases, showed that O. novo-ulmi consistently clustered most closely with the human pathogen Sporothrix schenckii, recently classified as a member of the mitosporic Ophiostomataceae. Disruption of the chsA gene locus had no obvious effects on the growth or morphology of the fungus.
Hintz
W E
WE
Biology Department, University of Victoria, BC, Canada. whintz@uvic.ca
D000595:Amino Acid Sequence; D001203:Ascomycota / Q000235:genetics*; D002687:Chitin Synthase / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology; D017386:Sequence Homology, Amino Acid; D013175:Sporothrix / Q000235:genetics* / Q000472:pathogenicity; D014197:Trees / Q000382:microbiology*
D002687:Chitin Synthase