化学反应工程与工艺
化學反應工程與工藝
화학반응공정여공예
CHEMICAL REACTION ENGINEERING AND TECHNOLOGY
2009年
5期
420-425
,共6页
宋希文%周治%姚忠%肖彦羚%徐虹%韦萍
宋希文%週治%姚忠%肖彥羚%徐虹%韋萍
송희문%주치%요충%초언령%서홍%위평
γ-谷氨酰转肽酶%固定化%γ-L-谷氨酰-L-半胱氨酸%酶法合成
γ-穀氨酰轉肽酶%固定化%γ-L-穀氨酰-L-半胱氨痠%酶法閤成
γ-곡안선전태매%고정화%γ-L-곡안선-L-반광안산%매법합성
γ-glutamyltranspeptidase%immobilization%γ-L-glutamyl-L-cysteine%enzymatic synthesis
以环氧基树脂Eupergit C250L为载体对B.subtilis NX-2 GGT进行了共价固定化.固定化酶的最适作用pH为9.0,最适作用温度为60℃.固定化酶的热稳定性和贮存稳定性均较游离酶有显著的提高,经100 d 20个批次转化后,固定化残余酶活仍能保持初始值的80%左右.以固定化酶为催化剂,在反应条件为L-谷氨酰胺(Gln)20 mmol/L、S-苄基-半胱氨酸(S-Bzl-cys)20 mmol/L、酶浓度0.0375 U/mL和pH 9.0条件下,40℃水浴反应22 h,转肽产物S-苄基-y-L-谷氨酰-L-半胱氨酸(S-Bzl-GGC)得率为4.3 mmol/L,较游离酶提高了11.96%.S-Bzl-GGC经酸解脱除保护基后可得γ-L-谷氨酰-L-半胱氨酸,产物纯度可达94.1%.
以環氧基樹脂Eupergit C250L為載體對B.subtilis NX-2 GGT進行瞭共價固定化.固定化酶的最適作用pH為9.0,最適作用溫度為60℃.固定化酶的熱穩定性和貯存穩定性均較遊離酶有顯著的提高,經100 d 20箇批次轉化後,固定化殘餘酶活仍能保持初始值的80%左右.以固定化酶為催化劑,在反應條件為L-穀氨酰胺(Gln)20 mmol/L、S-芐基-半胱氨痠(S-Bzl-cys)20 mmol/L、酶濃度0.0375 U/mL和pH 9.0條件下,40℃水浴反應22 h,轉肽產物S-芐基-y-L-穀氨酰-L-半胱氨痠(S-Bzl-GGC)得率為4.3 mmol/L,較遊離酶提高瞭11.96%.S-Bzl-GGC經痠解脫除保護基後可得γ-L-穀氨酰-L-半胱氨痠,產物純度可達94.1%.
이배양기수지Eupergit C250L위재체대B.subtilis NX-2 GGT진행료공개고정화.고정화매적최괄작용pH위9.0,최괄작용온도위60℃.고정화매적열은정성화저존은정성균교유리매유현저적제고,경100 d 20개비차전화후,고정화잔여매활잉능보지초시치적80%좌우.이고정화매위최화제,재반응조건위L-곡안선알(Gln)20 mmol/L、S-변기-반광안산(S-Bzl-cys)20 mmol/L、매농도0.0375 U/mL화pH 9.0조건하,40℃수욕반응22 h,전태산물S-변기-y-L-곡안선-L-반광안산(S-Bzl-GGC)득솔위4.3 mmol/L,교유리매제고료11.96%.S-Bzl-GGC경산해탈제보호기후가득γ-L-곡안선-L-반광안산,산물순도가체94.1%.
γ-glutamyltranspeptidase(GGT)from B.subtilis NX-2 was immobilized onto Eupergit C250L via oxirane method.The optimal pH and temperature of immobilized GGT were 9.0 and 60℃.The thermal and storage stability of GGT were significantly increased after immobilization.The activity of remaining GGT was still exceed 80%of its initial activity after storage for 100 d and reused for 20 batches.At the conditions of γ-Glutamine 20 mmol/L,S-benzyl-cysteine(S-Bzl-cys)20 mmol/L,immobilized GGT 0.0375 U/mL and pH 9.0,a maximal product yield of 4.3 mmol/Lwas obtained after incubated at 40℃ for 22 h,resulting in an increase of 11.96%compared to that use free GGT as catalyst.The protecting group of S-Bzl-γ-L-glutamyl-L-cysteine was removed with trifluoromethanesulfonic acid.The purity of produced γ-L-glutamyl-L-cysteine(GGC)was 94.1%.
