Title: Molecular characterization of TatD DNase gene from Staphylococcus pasteuri RA3T

Abstract

Staphylococcus pasteuri strain RA3^T a gram positive, non-spore forming, non-motile, catalase positive was isolated from surface soil. The identification of the bacterium was confirmed with 16S rDNA phylogeny and biochemical tests. TatD is shown to be a cytoplasmic protein and exhibits magnesium-dependent DNase. The TatD family has no involvement in protein export by the Tat system. A TatD DNase gene was isolated and cloned from Staphylococcus pasteuri strain RA3^T genome. Nucleotide sequence analysis revealed 774 nucleotides in length encoded for a protein of 257 amino acid residues. The TatD gene showed a high similarity to homologs belongs to Staphylococcus warneri SG1. The deduced polypeptide sequence harbors a typical catalytic site, HHRPEDHRHFSSGEDPLN and its calculated molecular mass and its predicted isoelectric point are 29656.7 Da and 5.05, respectively. The deduced amino acid sequence showed a high degree of similarity to TatD DNase isoforms from Staphylococcus genus and other sources. Three dimensional predictions of TatD confirmed active site and theoretical functions as DNase.