Molecular analysis of DNA polymorphism of Sporothrix schenckii.

Abstract

Partial cDNA cloning of a putative membrane transporter protein gene expressed in Sporothrix schenckii and DNA polymorphism of the isolated gene are described here. DNA fragments were isolated from S. schenckii, and the deduced amino acid sequence from one of the fragments contained a region homologous to the conserved sequence of the membrane transporter protein family. 188-bp fragments encoding the homologous region were amplified from many strains of S. schenckii, and were subjected to polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) analysis. The results demonstrated that the strains of S. schenckii were divided into three groups, and several base substitutions among these groups were observed. This finding agreed with the classification of S. schenckii strains based on the mitochondrial DNA diversity, because the three groups were clearly located on the branches of the phylogenetic tree constructed by digestion profiles of mitochondrial DNA with restriction enzymes. The correlation of the results of PCR-SSCP analysis with the mitochondrial DNA diversity might indicate linkage of the mutation of the membrane transporter protein gene with the evolution of S. schenckii, suggesting the protein plays an essential role in S. schenckii.