Numerical analysis of electrophoretic protein patterns of methicillin-resistant strains of Staphylococcus aureus

Abstract

A total of 50 strains of Staphylococcus aureus, including 41 methicillin-resistant S. aureus (MRSA) strains, were characterized by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell proteins. The protein patterns contained 40 to 50 discrete bands and were highly reproducible. Partial patterns were used as the basis of a computer-assisted numerical analysis. The MRSA strains clustered into four phenons at the 83% similarity level; and further division of phenon 1, at the 86% similarity level, resulted in a total of six clusters. All of the MRSA isolates from an MRSA epidemic in the United Kingdom were found to cluster in phenon 1 together with 9 of the 12 MRSA isolates from eastern Australia and 3 other MRSA isolates from the United Kingdom. The remaining three eastern Australian isolates clustered separately in phenon 2. Phenon 3 appeared to be exclusive to strains that were both susceptible and resistant to methicillin and that reacted with group V phages, and phenon 4 comprised 11 isolates, all of which were other MRSA isolates from the United Kingdom. We conclude that computer-assisted numerical analysis by high-resolution sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell proteins provides additional criteria for the study of the epidemiology and the evolution of MRSA.

Epidemiologic typing and delineation of genetic relatedness of methicillin-resistant Staphylococcus aureus by macrorestriction analysis of genomic DNA by using pulsed-field gel electrophoresis

“…These isolates were maintained freeze-dried in the collection of the Institut Pasteur du Brabant, Brussels, Belgium. In addition, the following unrelated MRSA isolates (n = 10) of diverse geographical origins (8,20) and collected between 1960 and 1987 were kindly provided by R. Marples from the collection of the Central Public Health Laboratory, London, England: E2, E03/M307, 85/2147, 85/5484, 84/9580, 85/4670, 85/1836, and 85/1774. Strains NCTC 10442 and NCTC 11940 were purchased from the National Collection of Type Cultures, Central Public Health Laboratory.…”

Analysis of methicillin-resistant and methicillin-susceptibleStaphylococcus aureusby a molecular typing method based on coagulase gene polymorphisms

“…A variety of systems, such as antimicrobial susceptibility patterns (antibiogram) [2,4], phage typing [22,23], capsular polysaccharide serotyping [24], zymotyping [25], protein analysis [26] and plasmid typing [5] have been used to type S. aureus. Antibiogram and phage typing are commonly used in epidemiological study, however, the former is often inadequate to differentiate strains, and the latter is limited by reproducibility and the frequent occurrence of untypable strains [3,4].…”

DNA‐DNA hybridization and analysis of restriction endonuclease and rRNA gene patterns of atypical (catalase‐weak/negative) Campylobacter jejuni from paediatric blood and faecal cultures

“…Pharmacia-LKB Biotechnology, Uppsala, Sweden) and previously described methods were used to compare each of the traces and to compute similarities (Owen et al 1989a;Costas et al 1989). Similarities between all possible pairs of fingerprints were expressed as the Pearson product moment correlation coefficient ( Y ) converted to a percentage value for convenience, Strains were then clustered by the method of unweighted pair group average (UPGMA) linkage.…”