Use of Commercial Enzyme Kits and Fatty Acid Production for the Identification of Serpulina Hyodysenteriae: A Potential Misdiagnosis

Abstract

Abstract. The accuracy of identification of Serpulina hyodysenteriae strains grown in a complex medium was 90% when 2 commercial test kits were used. Unlike the other S. hyodysenteriae strains, S. hyodysenteriae strain P35/2 was unusual in being indole negative. The nonpathogenic intestinal spirochete PWS/A, which is from a different species, was indole positive and α-galactosidase negative. Identification of these spirochetes on the basis of these kits alone would have been incorrect. The analysis of volatile fatty acids by gas chromatography showed that the ratio of acetic to butyric acid was from 11:1 to 44:1 for S. hyodysenteriae strains, which distinguished them from the other spirochetes. The exception was PWS/A (acetic : butyric of 32:1), but this spirochete, unlike the S. hyodysenteriae spirochetes, also produced isobutyric acid. Short chain fatty acid (SCFA) analysis by high-performance liquid chromatography detected different SCFAs in addition to acetic and butyric acids. These additional SCFAs did not contribute to further differentiation of the porcine spirochetes.

Outer membrane-associated serine protease of intestinal spirochetes

“…The peptide cleavage patterns produced by the OM‐associated spirochetal protease was similar to members of the subtilases, a superfamily of subtilisin‐like serine proteases. This is not inconsistent with previous reports indicating aminopeptidase activities among intestinal spirochetes [16–20]. However, these studies used commercially available rapid multi‐well systems for general identification of bacteria such as APIZYM, RapID‐ANAII, ANI card and An‐Ident systems, and none of the aminopeptidase specificities were consistently observed or characterized further.…”

“…Proteolytic cleavage of extracellular matrix proteins has been proposed as a mechanism of tissue damage in periodontitis associated with T. denticola [15]. Aminopeptidase, trypsin‐ and chymotrypsin‐like activities have been identified among S. hyodysenteriae , S. innocens , and some uncharacterized human and porcine intestinal spirochetes [16–20], but the activities have not been characterized. The objective of this study was to assess pathogenic and commensal intestinal spirochetes of humans and animals for protease activity.…”

Certain canine weakly beta-hemolytic intestinal spirochetes are phenotypically and genotypically related to spirochetes associated with human and porcine intestinal spirochetosis

“…Growth inhibition of the canine WBHIS on selective BJ medium was attributable to sensitivity to the macrolide antibiotic spiramycin ( Table 1). Sensitivity to the antibiotic spectinomycin accounts for the growth inhibition of S. innocens isolate B256 on the CVS and BJ selective media, as previously reported (25). Although Kunkle and Kinyon (20) did not observe a complete growth inhibition of S. innocens isolate B256 in BJ medium, a greater than 10 5 depression of viable cell numbers, from 3 ϫ 10 8 to Ͻ 1 ϫ 10 3 CFU/ml, was reported with the BJ medium compared with the TSA medium.…”