Open AccessBiotyping of Enterotoxigenic Staphylococcus aureus by Enterotoxin Gene Cluster ( egc ) Polymorphism and spa Typing Analyses
Author(s) -
Giuseppe Blaiotta,
Vincenzina Fusco,
Christof von Eiff,
Francesco Villani,
Karsten Becker
Publication year - 2006
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.00773-06
Subject(s) - enterotoxin , typing , microbiology and biotechnology , staphylococcus aureus , biology , genetics , gene , bacteria , escherichia coli
Thirty-fiveStaphylococcus aureus strains, including 10 reference strains and 25 strains recovered from clinical specimens and food samples, were analyzed by PCR REA (restriction endonucleases analysis) of theegc operon andspa typing. Nineteenspa types and seven differentegc operons, including four putative newegc variants, were revealed. In 13 strains, allelic variants ofsei and/orseg were found. By an analysis of their nucleotide sequence identities, a new homogeneous cluster of asei variant, called thesei variant, was detected in six strains. In addition, the prototypesei was shown to be more polymorphic than assumed so far. Seven strains possessed the recently describedseg variant, also exhibiting several nucleotide exchanges.spa typing was more effective than REAegc grouping as a typing technique. Since, in some cases, the REA typing method was able to discriminate strains showing the samespa type, it must be considered for PCR approaches involved in diagnostic procedures and may be useful for epidemiological studies. Hence, the polyphasic approach used in this study can be reliably and advantageously applied for typingegc -positiveS. aureus strains.