CAJ | 학술논문

从豆瓣酱中筛选出一株能高效降解亚硝酸盐的菌株LJ01，经鉴定为蜡样芽孢杆菌．通过测定LJ01细胞中不同组分的酶活，研究了亚硝酸盐还原酶的初步定位．LJ01经100 mg／L的NaNO2诱导后，用溶菌酶破壁，粗酶液先经阴离子DEAE Sepharose Fast Flow层析柱分离，测定不同蛋白组分a、b、c降解亚硝酸盐的活力，利用0．1 mol／L无机电子供体丁二酸和亚硫酸钠等鉴定出组分c为亚硝酸盐还原酶，再经葡聚糖凝胶G-150层析柱分离，获得较纯的亚硝酸盐还原酶，每升发酵液可得到0．54 mg活性酶蛋白，酶蛋白活力达到4004．89 U／mg，得率为2．37％，纯化后其NiR的比活力提高了17．57倍．经SDS-PAGE电泳后确定LJ01中亚硝酸盐还原酶的单体分子质量约为30 ku．
종두판장중사선출일주능고효강해아초산염적균주LJ01，경감정위사양아포간균．통과측정LJ01세포중불동조분적매활，연구료아초산염환원매적초보정위．LJ01경100 mg／L적NaNO2유도후，용용균매파벽，조매액선경음리자DEAE Sepharose Fast Flow층석주분리，측정불동단백조분a、b、c강해아초산염적활력，이용0．1 mol／L무궤전자공체정이산화아류산납등감정출조분c위아초산염환원매，재경포취당응효G-150층석주분리，획득교순적아초산염환원매，매승발효액가득도0．54 mg활성매단백，매단백활력체도4004．89 U／mg，득솔위2．37％，순화후기NiR적비활력제고료17．57배．경SDS-PAGE전영후학정LJ01중아초산염환원매적단체분자질량약위30 ku．
A strain LJ01 with strong nitrite degradation ability was isolated from fermented bean paste and was iden-tified as Bacillus cereus.Then, the primary cell localization of this nitrite reductase was examined by measuring the enzyme activity of different cellular components from LJ 01 cell.After LJ01 was induced by 100 mg/L sodium nitrite solution and treated with lysozyme , the crude enzyme solution of LJ 01 was first separated by means of the anion DEAE Sepharose Fast Flow chromatography , and the nitrite degradation activity of fractions a , b and c was measured.Moreover, by using inorganic electron donors such as 0.1 mol/L succinic acid and sodium sulfite solu-tion, fraction c was identified as a critical nitrite reductase and was separated by Sephadex G-150 column to get pure protein.The identification results show that 0.54 mg of active enzyme protein with an activity of 4004.89 U/mg can be obtained from 1 L of the fermentation liquid , and that the specific NiR activity of the purified enzyme increa-ses by 17.57 folds with a recovery of 2.37%.In addition , SDS-PAGE results show that the monomer molecular mass of LJ01 is about 30 ku.