TITLE:
New Spa Types among MRSA and MSSA Isolates in North of Iran
AUTHORS:
Fatemeh Shakeri, Ezzat Allah Ghaemi
KEYWORDS:
S. aureus, Spa Types, Healthy Carrier, MRSA, New Type
JOURNAL NAME:
Advances in Microbiology,
Vol.4 No.13,
October
14,
2014
ABSTRACT: Staphylococcus
aureus typing using gene encoding protein A (spa typing) seems to have a high potential discriminatory power for
typing this bacterium. This study was designed based on spa typing
method to compare the S. aureus types among healthy carrier vs patients,
and MRSA vs MSSA isolates. Method: This study was carried out on 182 spa typeable S. aureus isolates, including 52 MRSA. DNA was extracted by
phenol chloroform-isoamyl alcohol method and it was amplified by specific
primer of polymorphic X region of spa. Spa types were determined
by Ridom Staph Type software. The spa types distribution among
MRSA vs MSSA and healthy carrier vs patients, isolates were statistically
compared by X2 method and P spa in our region were t037 (18.3%) and t937
(13.9%) from 50 spa types which were identified in this study. spa types in this study were isolated from various age groups but t660 spa types
were only isolated from children. Distribution of all spa types among
MRSA and MSSA isolates was 16 and 38 types, respectively which is significant.
In this study we found seven new spa types (belong to twelve isolates)
which are reported for the first time. In 5
out of the above 7 new types the 24 bp repeated sequences in spa gene X region were already recognized but their 24 bp arrangement is introduced
in our present investigation. In the remaining 2 new types we found new 24 bp
nucleotide sequences which are also introduced for the first time in our
present study. Conclusion: The distribution of spa types in MSSA strains
was significantly higher than MRSA isolates, but there are not any specific spa types for discrimination between MRSA and MSSA. The novelty of our study is the
introducing 7 new spa types including 2 new 24 bp repeated sequences in
the X region of spa gene.