EFFECT OF ETHYL PENTANOATE ON ANTI- QUORUM ACTIVITY OF EXTRACELLULAR PROTEIN SECRETED BY BACILLUS SUBTILIS ATCC11774

Nabilah Alhadi,Maryam Rehan,Hanina Noor,Salina Mat Radzi,Nur Anis Ayunni Khalid,Hairulshahril Muhamad

doi:10.29121/ijetmr.v5.i5.2018.232

Abstract

Antimicrobials agents at low concentration could stress out bacteria by inducing proteins production via regulating the transcription and translation process. The interruption of bacterial quorum sensing (QS), or cell-to-cell communication is known to have the potential to weaken the bacterial pathogenicity by inhibiting their communication. This study aims to explore the potential of synthetic antimicrobial compound, ethyl pentanoate in stimulating proteins production by Bacillus subtilis ATCC11774 as well as to determine the anti-QS activity of microbial proteins produced. The bacterial cells were exposed to 0.01 MIC of ethyl pentanoate in fermentation process at 37°C for 48 h and 72 h respectively. The proteins produced were further isolated and analyzed by using Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE). Results showed that a new extracellular protein with approximate size of 15 kDa was produced by B. subtilis ATCC11774 after being treated with ethyl pentanoate at 37°C for 48 h and 72h. Despites of new protein band production, there was a deletion of protein band with approximate size of 18 kDa on protein synthesized at 72 h of fermentation. Whilst, the anti-QS activity of microbial proteins produced by B. subtilis at 37°C for 48 h and 72 h was determined by agar- wells diffusion assay, resulting “halo” inhibition zone ranged from 10.00 ± 1.00 to 10.33 ± 0.56 in diameter. Therefore, B. subtilis ATCC11774 in the presence of ethyl pentanoate at 0.01 MIC could regulate the extracellular protein production and expression. The isolated protein also exhibited anti-QS activity.

Highlights

IntroductionBacteria may response to fluctuation of temperature, low concentration of nutrients available, oxygen stress of environment, cell envelope damage and other growth-compromising stresses, in which these unfavorable environmental conditions could stress out bacteria [1]
B. subtilis ATCC11774 was grown in the presence of ethyl pentanoate as stress inducer
The extracellular protein produced by B. subtilis ATCC11774 either with or without ethyl pentanoate treatments were expressed differently

Summary

Introduction

Bacteria may response to fluctuation of temperature, low concentration of nutrients available, oxygen stress of environment, cell envelope damage and other growth-compromising stresses, in which these unfavorable environmental conditions could stress out bacteria [1]. The bacteria will further undergo series of responses for them to survive in these stress environments. As a stress response, the bacteria may synthesize antibiotics and extracellular enzymes, biofilm formation, and induction of resistance mutations. In spore -forming bacteria such as B. subtilis, spore formation is the most dramatic response to stress condition, in which the heat-resistant spores could help them to survive [1; 2]. Antimicrobials are one of the stresses that could affect the bacterial growth. The bacteria may response to the antimicrobials by producing specific proteins such as bacteriocins for its survival. Antimicrobials agent at sub-minimal inhibitory concentration (sub-MIC) or low concentrations able to affect the gene transcription process by activating or repressing gene transcription and expression [3]

Objectives

Methods

Results