Enhanced production of extracellular ice nucleators from Erwinia herbicola

The Journal of General and Applied Microbiology

Jingkun Li¹  Tung-Ching Lee¹ 

[1] Department of Food Science and the Center for Advanced Food Technology, Rutgers University

关键词: Erwinia herbicola;    extracellular ice nucleators;    ice nucleation;   

DOI  :  10.2323/jgam.44.405

学科分类：微生物学和免疫学

来源: Applied Microbiology, Molecular and Cellulrar Biosciences Research Foundation

【 摘 要 】

The effects of growth conditions and chemical or physical treatments on the production of extracellular ice nucleators (ECINs) by Erwinia herbicola cells were investigated. The spontaneous release of ECINs, active at temperatures higher than −4°C, into the environment depended on culture conditions, with optimal production when cells were grown in yeast extract to an early stationary phase at temperatures below 22°C. ECINs were vesicular, released from cell surfaces with sizes ranging from 0.1 to 0.3 μm as determined by ultrafiltration and transmission electron microscopy. Protein profiles of ECIN fractions during bacterial growth were examined by SDS-polyacrylamide gel electrophoresis (SDS-PAGE), and Ina proteins were detected by Western blotting. ECIN production was enhanced 5-fold when cells were treated with EDTA and 20- to 30-fold when subjected to sonication. These conditions provide a means for large-scale preparations of ECINs by E. herbicola.

【 授权许可】

Unknown