Characterization of Serratia marcescens, S. liquefaciens, S. plymuthica and S. marinorubra by the Electrophoretic Patterns of their Esterases

Abstract

Esterases of 62 Serratia marcescens, S. liquefaciens, S. plymuthica and S. marinorubra strains were analysed by horizontal slab electrophoresis in polyacrylamide-agarose gel. Five principal bands hydrolysed P-naphthyl acetate but differed in their range of activity towards other substrates and in their sensitivity to di-isofluoropropyl phosphate. Additional bands were detected in some strains of S. marcescens and S. marinorubra. The comparative distribution of bands showed that the four Serratia species were characterized by distinct electrophoretic patterns of their esterases. Serratia marcescens, S. Ziquefaciens and S. plymuthica appeared to be more closely related to one another than to S. marinorubra. In the case of S.plymuthica and S. marinorubra, congruence was found between biovars and esterase patterns. The numerous electrophoretypes observed within Serratia species might provide useful epidemiological markers. I N T R O D U C T I O NPrevious investigations have revealed that esterases of several taxa in the family Enterobacteriaceae (Goullet, 1973(Goullet, , 1975(Goullet, , 1977Goullet & Richard, 1977) give distinct and reproducible species-specific zymogram banding patterns when assayed after electrophoresis in polyacrylamide-agarose gel. In the present study, the esterases produced by the four Serratia species recognized by Grimont et al. (1977a, b) were examined. METHODSThe names and sources of the test strains are given in Table 1. Growth conditions, preparation of extracts, inhibition by di-isofluoropropyl phosphate (DFP), protein estimation, acrylamide-agarose gel electrophoresis, esterase staining and estimation of electrophoretic mobility (MF value) have all been described previously (Goullet, 1977). RESULTSThe esterase profiles resolved from multiple runs of the same and different soluble extracts from each strain were reproducible. Electrophoretic relationships were established between the strains by numerous replicate assays comparing esterase bands in adjacent positions on the same gel. Esterase bands were found in all of the test strains.Five principle esterase bands varying in sharpness and colour intensity, designated as E,, E,, ES, E, and E, in order of decreasing electrophoretic mobility, were defined ( Fig. 1 a),The El band hydrolysed a-naphthyl acetate and to a lesser degree a-naphthyl butyrate, indoxyl acetate and P-naphthyl acetate; the Ez band hydrolysed a-and P-naphthyl acetates;

Antigenic Relationships Among Type-3 Fimbriae of Enterobacteriaceae Revealed by Immunoelectronmicroscopy

“…The types of fimbriae (and associated haemagglutinins) commonly found on most strains of Salmonella and Yersinia are, respectively, type-1 fimbriae (and MS-HA) and MR/Y fimbriae (and broad-spectrum MR/Y-HA) (Duguid et al, 1966;MacLagan and Old, 1980;Old and Adegbola, 1984b). It has long been known, however, that occasional strains of Salmonella subgenus I possess thin fimbriae, antigenically like those found on strains of Y. enterocolitica possessing K1 antigen (Rohde et al, 1975;AleksiC et al, 1976 and1978;Aleksii: and Aleksii:, 1979); the knowledge that these fimbriae were also MR/K-HAassociated and antigenically related to those of Klebsiella is more recent (Adegbola et al, 1983a). Furthermore, the thin fimbriae rarely found on occasional strains of Salmonella of subgenera I1 and I11 are unlike the type-3 fimbriae of Salmonella subgenus I in antigenicity (AleksiC et al, 1978), haemagglutinating activity (Adegbola et al, 1983a) and surface hydrophobicity (Dr S. AleksiC, personal communication).…”

“…marinorubra belonged to an antigenic group different from that of the other eight species of Serratia is perhaps not surprising, for Serr. marinorubra is poorly related to other Serratia species (Grimont et al, 1977a) and its esterases and proteases are also distinct (Grimont et al, 1977b;Goullet, 1978).…”

“…Similar MR/K-like haemagglutinins and associated type-3 fimbriae have now been described in many strains of most genera of the tribes Klesielleae and Proteeae (Duguid and Old, 1980;Adegbola and Old, 1982and 1985Old and Adegbola, 1982and 1984a. Furthermore, thin, type 3-like fimbriae have been found on a few strains of Salmonella and Yersinia, genera in which type-3 fimbriae are uncommon (Rohde et al, 1975;Aleksii: et al, 1976 and1978;Adegbola et al, 1983a).…”

Characterization of Enterobacteria by Esterase Specific-Activity Profiles

“…However, enzyme electrophoresis has been shown to be a powerful tool for studying classification, population genetics and epidemiology. Oxidoreductases were the first enzymes studied (Bowman et al, 1967 ;Baptist et al, 1969), but esterases have been more widely used; 36 species belonging to Escherichia (Goullet, 1973 ;, Shigella (Goullet, 1980b), Proteus and Providencia (Goullet, 1975;Goullet & Picard, 1985), Salmonella , Citrobacter (Goullet & Richard, 1977), Klebsiella, Enterobacter (Goullet, 1980 a ;, Serratia (Goullet, 1978(Goullet, , 1981 and Yersinia have been investigated. More recently, multilocus enzyme electrophoresis, analysing in particular oxidoreductases and transferases, has been used for comparisons between and within E. coli and Shigella (Ochman et al, 1983) and within Salmonella (Reeves et al, 1989;Beltran et al, 1989) and Serratia marcescens (Gargallo-Viola, 1989).…”

“…plymuthica (1 5 strains) and S. marinorubra (15 strains) (Goullet, 1978); S. odorifera (15 strains), S. ficaria (13 strains), S . fonticola (1 4 strains) (Goullet,198 1); Proteus uulgaris (1 2 strains), P. mirabilis (1 2 strains), Prooidencia stuartii (1 7 strains), P .…”