DJ Kalita, P Knowar, Satya Sarma , DJ Dutta and A Baruah
Assam Agricultural University, India
Posters & Accepted Abstracts: J Cell Signal
Statement of the Problem: The use of antibiotics as growth enhancers is a common practice in meat industry and extensive use of
antibiotic in the meat industry causes an alarming increase of antibiotic resistance microbes across the world. Antibiotic resistance
has been posing an increasingly serious concern to the public, health specialist, and animal food producers. Therefore, there is a need
for an alternative group of drugs which do not induce bacterial resistance and have no effect on the food chain. Antimicrobial peptides
particularly defensin and cathelicidin are prevalent throughout the nature as part of the intrinsic defenses of most organisms. In the
present study tissue samples of reproductive tract were collected from apparently healthy indigenous cattle (Bos indicus) from local
slaughter house to characterize the cathelicidin gene from the reproductive tract epithelial layer for in-silico designing and synthesis
of novel antimicrobial peptides from the predicted peptide.
Methodology & Theoretical Orientation: RNA was extracted from the reproductive tract epithelial layer and RT-PCR of extracted
RNA yielded a specific product of 530 bp for reproductive cathelicidin gene. The purified PCR product was cloned and positive clones
were sequenced at Sci Genom, Hyderabad. The cDNA sequence was compared using homologous sequences retrieved by BLAST. The
predicted peptide from complete ORF of reproductive tract cathelicidin gene was comprised of 144 amino acids. Active peptides of
Bos indicus reproductive tract cathelicidin was from 131-144 and this domain had 3 arginines, 1 lysine, 3 proline and 4 tryptophan.
Support Vector Machine (SVM) algorithm was used for designing and prediction of antimicrobial potency from the functional
peptide exist in the C-terminal domain of 131-144. Two peptides designed, synthesized and found to be effective against both gram
positive and negative bacteria. Minimum Inhibitory Concentration (MIC) of the antimicrobial peptides were determined on the
fresh culture of S. aureus, L. monocytogen, E. coli and S. Typhimurium. Cytotoxicity of the synthesized peptides was also recorded by
erythrocyte lysis ability at different concentrations (4, 40 and 80 μM) and was found to be less than 3% up to 40 μM concentration.
Conclusion & Significance: From the present study, it can be concluded that the epithelial layer of the reproductive tract of Bos
indicus synthesized a very potent antimicrobial peptide and this can be used as a blueprint for in-silico designing and synthesis of
short novel Antimicrobial peptides.
E-mail: djkalita@rediffmail.com
