Numerical analysis of electrophoretic protein patterns of Providencia rustigianii strains from human diarrhoea and other sources

Abstract

Twenty strains of Providencia rustigianii (including the type strain of Prov. friedericiana) have been characterized by one-dimensional SDS-PAGE of cellular proteins. They comprised 12 strains (almost exclusively associated with the intestinal tract) from humans, plus eight largely from the intestinal tract of pig, penguin and environmental sources. The protein patterns, which contained 45-50 discrete bands, were highly reproducible and were used as the basis for two numerical analyses. In the first, which included all the protein bands, the 20 Prov. rustigianii strains formed six clusters at the 88% S level. One of these clusters included the type strains of both Prov. friedericiana and Prov. rustigianii, thereby confirming the synonymy of these two species. In the second analysis, the principal protein bands were excluded. At the 86% S level the 20 Prov. rustigianii strains formed a single cluster, whilst a field strain of Morganella morganii and the respective type strains of three other Providencia species remained unclustered. The total protein pattern of the type strain of Prov. alcalifaciens was very similar to that of Prov. rustigianii phenon 3 and the M. morganii field strain, which indicates that careful biochemical characterization may be necessary to ascribe strains to a species before typing by the PAGE technique. Alternatively, a selective analysis of the protein bands may be used to confirm the identity of the strains, as shown in this study.

Numerical analysis of SDS–PAGE protein patterns ofSerratia marcescens: a comparison with other typing methods

“…The level of reproducibility achieved in this study was similar to that quoted as acceptable by Jackman [14] and was well above the minimum acceptable value [28]. Previous studies using similar methods have reported levels of at least 93 % similarity between duplicate samples in separate electrophoretic runs [17,21,25,26]. The dendrogram and protein types recognized in the analysis proved to be extremely robust when the computations were repeated using different levels of trace alignment and background subtraction.…”

“…The 25 t : s q q e s _ N _ { 1 e s I I I q q q q q q q q d q H H I I I _ _ _ _ > z I l I Serotyping and phage typing 0-serotyping and phage typing were performed using methods described previously [10,24]. Isolates were divided on the basis of 0-serotype and were then further sub-divided by phage typing.…”

Comparison of SDS–PAGE protein patterns with other typing methods for investigating the epidemiology of ‘Klebsiella aerogenes’

“…The level of reproducibility achieved in this study was higher than that quoted as acceptable by Jackman [1O] and was well above the minimum acceptable value [26]. Previous studies using similar methods have reported levels of at least 93 % similarity between duplicate samples in separate electrophoretic runs [13,19,23,24]. The dendrogram (Fig.…”

Application of physico-chemical typing methods for the epidemiological analysis ofSalmonella enteritidisstrains of phage type 25/17

“…However, the importance of WCPP for this purpose is differently assessed in the literature. Costas and colleagues [19] think it valuable, Olsen and co-workers [20] found it to be not very convincing at least in the case of S. berta. Similarly the efficiency of FT-IR spectroscopy is not yet unambiguously clarified.…”