Antibacterial Potential of a Basic Phospholipase A₂ (VRV-PL-V) of Daboia russellii pulchella (Russell’s Viper) Venom

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S. Sudarshan¹ and B. L. Dhananjaya^1,2*

¹Venom Research Unit, Adichunchanagiri Biotechnology and Cancer Research Institute (ABCRI), Balagangadharanatha Nagara, Mandya District, Karnataka 571 448, India

²Toxinology/Toxicology and Drug Discovery Unit, Center for Emerging Technologies, Jain Global Campus, Jain University, Kanakapura Taluk, Ramanagara-562112, Karnataka, India; fax: +91-80-2757-7199; E-mail: chandu_greeshma@rediffmail.com; chandudhananjaya@gmail.com

^* To whom correspondence should be addressed.

Received April 1, 2014; Revision received April 9, 2014

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Microbial/bacterial resistance against antibiotics is considered as a potentially serious threat to public health. Further, as these antibiotics elicit side effects, there is interest in developing new molecules with novel modes of action from diverse organisms. Along these lines, in this study the antibacterial potential of the basic protein VRV-PL-V (Vipera russellii venom phospholipase A₂ fraction V) of Daboia russellii pulchella venom was evaluated. VRV-PL-V demonstrated a potent antibacterial activity against all the human pathogenic strains tested. It inhibited more effectively Gram-positive bacteria like Staphylococcus aureus and Bacillus subtilis when compared to Gram-negative bacteria like Escherichia coli, Vibrio cholerae, Klebsiella pneumoniae, and Salmonella paratyphi. It inhibited bacterial growth with MIC values ranging from 13 to 24 µg/ml. The antibacterial potential of VRV-PL-V was comparable to the standards used like gentamycin, chloramphenicol, and streptomycin. There was a strong correlation between PLA₂ activities and hemolytic and antibacterial activity. It was found that even in the presence of p-bromophenacyl bromide (an inhibitor of PLA₂ enzymatic activity), there was marked antibacterial activity, suggesting dissociation or partial overlapping of the bactericidal/antimicrobial domains. Therefore, this study shows that although there is a strong correlation between enzymatic and antimicrobial activities of VRV-PL-V, it may also possess other properties that mimic bactericidal/membrane permeability-increasing protein.

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KEY WORDS: snake venom, phospholipase A₂, antimicrobial, Daboia russellii pulchella, human pathogenic bacteria

DOI: 10.1134/S000629791411011X

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