Ismatul Nurul Asyikin IsmailHanina Mohd NoorHairul Shahril MuhamadSalina Mat RadziAbdul Jalil Abdul KaderMaryam Mohamed RehanRosfarizan Mohamad2024-05-272024-05-2720131/9/20202329-3837http://www.wjst.org/WJSTR_Vol.%201,%20No.%208,%20October%202013/Protein%20Produced.pdfhttps://oarep.usim.edu.my/handle/123456789/3663Volume: 1 No: 8 (Page: 174 - 181)Previous studies have established that subinhibitory concentrations of antibiotics or antimicrobials are potent modulators of transcription process in bacterial cells. Hence, the bacteria might be introduced new proteins in mild stress environments like in the presence of antimicrobial agents at low concentrations. Although, there are still limited studies on the potential of antimicrobials at low doses play as a signaling agent that capable to modulate biological functions in bacteria. Therefore, this study aims to explore proteins production by Lactobacillus plantarum ATCC 8014 during stress which is in the presence of ethyl pentanoate at sub-minimal inhibitory concentration (sub-MIC). The Minimum Inhibition Concentration (MIC) of ethyl pentanoate against L. plantarum is 14.29% and was performed by microdilution assay. L. plantarum cells were treated with ethyl pentanoate at sub-MIC (0.05 x MIC) in the fermentation process. Two new protein bands (approximate size of 46.51 kD and 6.91 kD) were detected for the treated bacteria showed by SDS-PAGE profile. Of the two bands, eight possible proteins were identified by LC-MS/MS analysis. Thus, L. plantarum ATCC 8014 capable to produce new proteins in mild stress condition with the presence of 0.05 x MIC ethyl pentanoate. Futhermore, the isolated microbial proteins exhibit antimicrobial activity against several Gram-positive and Gram-negative bacteria. Copyright © WJSTR, all rights reserved.enantimicrobial, transcription, mild stress, sub-MIC, proteins, Lactobacillus plantarum ATCC 8014, ethyl pentanoateArticle17418118