10.22376/ijpbs.2019.10.1.p1-12 Volume 5 Issue 3 2014 (July- September) lessThan i greaterThan Acinetobacter lessThan /i greaterThan is one of the important opportunistic pathogens involved in hospital acquired infection. They cause various types of human infections leading to morbidity and mortality. Of these lessThan i greaterThan Acinetobacter lessThan /i greaterThan species, lessThan i greaterThan Acinetobacter baumannii lessThan /i greaterThan is the most prevalent in clinical specimens causing pneumonia. It is very common among inpatients admitted in ICUs for various ailments. Around hundred sputum samples were collected from patients visiting various hospitals of Kanyakumari District, Tamil Nadu. From this clinical specimen, 16 were identified preliminarily as lessThan i greaterThan Acinetobacter baumannii by lessThan /i greaterThan various morphological and biochemical tests. The identities of the bacterial isolates were confirmed by 16S rRNA sequence analyses. Antibiotic susceptibility testing was performed by the agar disc diffusion method. Variations were observed in the resistance pattern of the bacterial isolates towards various commercial antibiotics. The genetic variability of lessThan i greaterThan Acinetobacter baumannii lessThan /i greaterThan isolates were detected using RAPD assay. The RAPD assay using different primers showed distinct molecular variation among the 16 isolates suggesting the emergence of new resistant strains among the clinical isolates S.K.SUNDAR, T.P.KUMARI PUSHPA RANI, B.VIJAYALAKSHMI AND M. MURUGAN A. baumannii, RAPD, Genetic variability, Antibiotic susceptibility 744-751