The emergence of Acinetobacter baumannii ST-6 multidrug resistant: A resilient biofilm producer, Malaysia
- Author:
Jayakayatri Jeevajothi Nathan
;
Mohd Nasir Mohd Desa
;
Voon Chen Yong
;
Parasakthi Navaratnam
;
Navindra Kumari Palanisamy
;
Eng Hwa Wong
- Publication Type:Journal Article
- Keywords:
Acinetobacter baumannii;
multilocus sequence typing;
multidrug-resistant;
biofilm
- MeSH:
Acinetobacter baumannii
- From:Malaysian Journal of Microbiology
2016;12(4):265-269
- CountryMalaysia
- Language:English
-
Abstract:
Aims: The aim of this research is to explore the presence of multidrug-resistance (MDR) Acinetobacter baumannii
strains isolated from hospitalized patients in a tertiary-care center, Subang Jaya, Selangor, Malaysia and to compare
their genotypic and phenotypic characteristics.
Methodology and results: Clonal relationships were determined by multilocus sequence typing (MLST) and biofilm
forming ability was evaluated by using 2, 3 - bis (2 - methoxy - 4 - nitro - 5-sulfophenyl) - 5 - [(phenylamino) carbonyl] -
2H-tetrazolium hydroxide (XTT) reduction assay in microplates and Congo red agar method (CRA). Four virulence
genes coding for A. baumannii pilus usher-chaperone assembly protein, csuE gene; outer membrane protein, ompA
gene; biofilm poly-β-1, 6-Nacetylglucosamine (PNAG) synthesis protein, pgaA gene; and acinetobactin-mediated iron
acquisition protein, bauA gene were searched for in a collection of strains. Antimicrobial resistance against 11 antibiotics
were studied by broth microdilution method. Seventeen A. baumannii clinical strains were isolated and MLST showed
that the strains belonged to 5 distinct sequence types (STs), namely, ST-6, ST-265, ST-324, ST-325 and ST-432. Fiftythree
percent of the strains were resistant to 4 or more antibiotics. Twelve strains produced biofilm and out of them, 4
were strong biofilm producer, besides, these strong biofilm producers were MDR strains and belongs to ST-6. In
addition, all strains were ompA positive, biofilm producing strains were csuE and pgaA positive and only strong biofilm
producing strains were bauA positive.
Conclusion, significance and impact study: Our study demonstrates that the ST-6 strains in Malaysia could represent
MDR, capable of forming strong biofilm and possess csuE, ompA, pgaA and bauA genes, virulence characteristics that
probably help the bacteria to persist and cause infection.
- Full text:P020170105494134175037.pdf