Structural Comparison of Ten Serotypes of Staphylocoagulases in Staphylococcus aureus

Abstract

Staphylocoagulase detection is the hallmark of a Staphylococcus aureus infection. Ten different serotypes of staphylocoagulases have been reported to date. We determined the nucleotide sequences of seven staphylocoagulase genes (coa) and their surrounding regions to compare structures of all 10 staphylocoagulase serotypes, and we inferred their derivations. We found that all staphylocoagulases are comprised of six regions: signal sequence, D1 region, D2 region, central region, repeat region, and C-terminal sequence. Amino acids at both ends, 33 amino acids in the N terminal (the signal sequences and the seven N-terminal amino acids in the D1 region) and 5 amino acids in the C terminal, were exactly identical among the 10 serotypes. The central regions were conserved with identities between 80.6 and 94.1% and similarities between 82.8 and 94.6%. Repeat regions comprising tandem repeats of 27 amino acids with a 92% identity on average were polymorphic in the number of repeats. On the other hand, D1 regions other than the seven N-terminal amino acids and D2 regions were less homologous, with diverged identities from 41.5 to 84.5% and 47.0 to 88.9%, respectively, and similarities from 53.5 to 88.7% and 56.8 to 91.9%, respectively, although the predicted prothrombin-binding sites were conserved among them. In contrast, flanking regions of coa were highly homologous, with nucleotide identities of more than 97.1%. Phylogenetic relations among coa did not correlate with those among the flanking regions or housekeeping genes used for multilocus sequence typing. These data indicate that coa could be transmitted to S. aureus, while the less homologous regions in coa presumed to be responsible for different antigenicities might have evolved independently.

Genome Sequence of Staphylococcus aureus Strain Newman and Comparative Analysis of Staphylococcal Genomes: Polymorphism and Evolution of Two Major Pathogenicity Islands

“…Staphylococcal diversity is mainly due to polymorphisms that occur in genomic islands, which also carry many virulence and antibiotic resistance determinants. Nevertheless, some genes, such as the staphylocoagulase gene, are located outside of genomic islands and are known to be polymorphic (32). One can add to this list certain combinations of virulence genes, for example, seh (enterotoxin H) and cna (collagen-binding protein), which are present only in certain types of S. aureus strains.…”

Type I Signal Peptidase and Protein Secretion in Staphylococcus aureus

“…The secretion of several additional virulence factors was also inhibited by the arylomycin, including two lipases (Lip1 and Lip2, SAOUHSC_00300 and SAOUHSC_03006, respectively), the autolysins Sle and Atl (SAOUHSC_00427 and SAOUHSC_00994, respectively), an N-acetylmuramoyl-L-alanine amidase (SAOUHSC_ 02979), 1-phosphatidylinositol phosphodiesterase (Plc; SAOUHSC_ 00051), glycerophosphoryl diester phosphodiesterase (GlpQ; SAOUHSC_00897), hyaluronate lyase (HysA; SAOUHSC_02463, hysA), staphylokinase (SAOUHSC_02171), thermonuclease (Nuc; SAOUHSC_00818), staphylocoagulase (SAOUHSC_00192), fibronectin binding protein (Efb; SAOUHSC_01114), immunodominant staphylococcal antigen B (IsaB; SAOUHSC_02972), and the immunoglobulin G-binding protein (Sbi; SAOUHSC_ 02706) (47,48,57,66,67,77,92,106,112). In addition, we identified two hypothetical proteins that are secreted in an SPase-dependent manner, SAOUHSC_00256 and SAOUHSC_00617, suggesting that they should be investigated as potential virulence factors.…”

mecA -Positive Staphylococcus aureus with Low-Level Oxacillin MIC in Taiwan

“…All isolates were first confirmed to be S. aureus by coagulase PCR (29). The mecA gene was determined by PCR by using the primers mA1 and mA2 according to a previously published protocol (17).…”