1. Improved antimicrobial activities of synthetic-hybrid bacteriocins designed from enterocin E50-52 and pediocin PA-1
Santosh Kumar Tiwari, Katia Sutyak Noll, Veronica L Cavera, Michael L Chikindas Appl Environ Microbiol. 2015 Mar;81(5):1661-7. doi: 10.1128/AEM.03477-14. Epub 2014 Dec 19.
Two hybrid bacteriocins, enterocin E50-52/pediocin PA-1 (EP) and pediocin PA-1/enterocin E50-52 (PE), were designed by combining the N terminus of enterocin E50-52 and the C terminus of pediocin PA-1 and by combining the C terminus of pediocin PA-1 and the N terminus of enterocin E50-52, respectively. Both hybrid bacteriocins showed reduced MICs compared to those of their natural counterparts. The MICs of hybrid PE and EP were 64- and 32-fold lower, respectively, than the MIC of pediocin PA-1 and 8- and 4-fold lower, respectively, than the MIC of enterocin E50-52. In this study, the effect of hybrid as well as wild-type (WT) bacteriocins on the transmembrane electrical potential (ΔΨ) and their ability to induce the efflux of intracellular ATP were investigated. Enterocin E50-52, pediocin PA-1, and hybrid bacteriocin PE were able to dissipate ΔΨ, but EP was unable to deplete this component. Both hybrid bacteriocins caused a loss of the intracellular concentration of ATP. EP, however, caused a faster efflux than PE and enterocin E50-52. Enterocin E50-52 and hybrids PE and EP were active against the Gram-positive and Gram-negative bacteria tested, such as Micrococcus luteus, Salmonella enterica serovar Enteritidis 20E1090, and Escherichia coli O157:H7. The hybrid bacteriocins designed and described herein are antimicrobial peptides with MICs lower those of their natural counterparts. Both hybrid peptides induce the loss of intracellular ATP and are capable of inhibiting Gram-negative bacteria, and PE dissipates the electrical potential. In this study, the MIC of hybrid bacteriocin PE decreased 64-fold compared to the MIC of its natural peptide counterpart, pediocin PA-1. Inhibition of Gram-negative pathogens confers an additional advantage for the application of these peptides in therapeutics.
2. Production of bacteriocin E50-52 by small ubiquitin-related modifier fusion in Escherichia coli
Qing Wang, Wenjuan Fu, Qingshan Ma, Zhanqiao Yu, Rijun Zhang Pol J Microbiol. 2013;62(4):345-50.
Bacteriocin E50-52, a class IIa bacteriocin with a wide antibacterial spectrum, and has a huge potential to be a substitute for convention. antibiotics. In this research, the bacteriocin E50-52 gene was cloned into the expression vector pET SUMO (small ubiquitin-related modifier) and introduced into Escherichia coli BL21 (DE3). The recombinant fusion protein SUMO-bacteriocin E50-52 expressed in a soluble form was purified to a purity of more than 90% by Ni-NTA sepharose column and 117 mg fusion protein was obtained per liter of fermentation culture. The fusion protein was cleaved with SUMO protease and re-applied to a Ni-NTA Sepharose column. Finally, about 16 mg recombinant bacteriocin E50-52 (rbE50-52) was obtained from a 1-liter fermentation culture with no less than 95% purity. The rbE50-52 had similar antimicrobial properties and molecular weight as the native bacteriocin E50-52 and showed very low hemolytic activity.
