Characterization of Extracellular Proteolytic Enzyme of Isolated Psychrotrophic Bacteria from Cheddar Cheese

체다치즈에서 분리한 내냉성미생물의 단백질분해효소의 특성

  • Published : 1991.08.01

Abstract

Psychrotrophs producing protease were isolated during ripening periods of Cheddar cheese and one of them containing the highest protease activity was identified as Pseudomonas fluorescens 65. The extracelluar proteolytic enzyme was partially purified from P. fluorescens 65 through the Sephadex G-100 gel filtration. The protease was eluted between 190 ml and 230 ml of elution volume of sodium phosphate buffer. The purified protease showed a single band in SDS-PAGE and its molecular weight was 47,000. The composition of amino acid for the protease was determined and the most abundant amino acids were glutamic acid (14.96%) and serine (13.86%). The optimum temperature and pH for the activity was $45{\sim}50^{\circ}C$ and 6.0, respectively.

Keywords

Cheddar cheese;ripening period;psychrotrophs;protease activity;P. fluoresecens