Activity assay for nisin-like acidic bacteriocins using an optimal pH-conditioned gel matrix.
A new zymography for detecting nisin-like acidic bacteriocins was developed using a tricine-sodium dodecyl sulfate (SDS) gel and an acidic gel matrix (pH 4.0). After electrophoresis, proteins in the tricine gel were electrotransferred to an optimal pH-conditioned gel matrix (OP-CGM). The OP-CGM was overlaid with indicator cells (Bacillus cereus) embedded in nutrient broth soft agar (0.8%, w/v). Antibacterial activity shown as a growth inhibition using B. cereus was detected at approximately 3.8kDa. Because nisin is unstable in buffers at pH values over 6.0, the common electrophoretic systems, SDS-polyacrylamide gel electrophoresis and tricine gel, are not suitable for detection of nisin-like acidic bacteriocins.
Institute Bioindustry Research Center, KRIBB, Jeonbuk 580-185, Republic of Korea.
Nack-Shick
NS
Choi
Seong-Yeop
SY
Jeong
Hee-Jong
HJ
Yang
Keug-Hyun
KH
Ahn
Chan-Sun
CS
Park
Cha Young
CY
Kim
Joong Su
JS
Kim
Byung-Dae
BD
Yoon
Min-Soo
MS
Kim
D000143:Acids; D001409:Bacillus cereus / Q000187:drug effects; D001430:Bacteriocins / Q000032:analysis* / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D006863:Hydrogen-Ion Concentration; D009561:Nisin / Q000032:analysis
D000143:Acids; D001430:Bacteriocins; D009561:Nisin