食品安全质量检测学报
食品安全質量檢測學報
식품안전질량검측학보
FOOD SAFETY AND QUALITY DETECTION TECHNOLOGY
2015年
6期
2323-2329
,共7页
张新武%侯钢北%杨晓明%廉娜娜
張新武%侯鋼北%楊曉明%廉娜娜
장신무%후강북%양효명%렴나나
L-色氨酸%营养缺陷型%菌株选育%产酸率%交叉反馈抑制
L-色氨痠%營養缺陷型%菌株選育%產痠率%交扠反饋抑製
L-색안산%영양결함형%균주선육%산산솔%교차반궤억제
L-tryptophan,auxotroph%strains selected breeding%acid production rate%cross-feedback inhibition
目的：以谷氨酸棒杆菌(Corynebacterium glutamicum)HX-22为出发菌株,研究了目标发酵产物L-色氨酸合成途径交叉反馈抑制途径代谢突变与色氨酸分解代谢类似物抗性的营养缺陷型突变诱导过程及 L-色氨酸高产复合突变菌株的筛选。方法采用硫酸二乙酯、紫外线、钴60γ-射线等诱变方法交叉处理起始与突变菌株,通过营养缺陷表型和自杀代谢底物抗性的筛选方法,定向突变和选育 L-色氨酸合成与分解代谢突变的色氨酸高产菌株。结果通过多次连续营养缺陷型诱变选育,筛选出一株具有分支酸-Trp/Phe/Tyr代谢途径L-Phe和 L-Tyr 合成缺陷型和 L-Trp 分解代谢自杀代谢底物抗性的 L-色氨酸高产菌 HX22-118(?Phe--?Tyr--5FTr-4FPr-SGr)；通过连续传代10次发酵,色氨酸产酸最高达到28.4 g/L,平均27.1 g/L,较出发菌株HX22产酸水平提高81.8%。结论选育出的高产菌株具有多重代谢途径突变(?Phe--?Tyr--5FTr-4FPr-SGr),突变体具有良好的遗传稳定性,具有后续工业化生产应用潜力。
目的：以穀氨痠棒桿菌(Corynebacterium glutamicum)HX-22為齣髮菌株,研究瞭目標髮酵產物L-色氨痠閤成途徑交扠反饋抑製途徑代謝突變與色氨痠分解代謝類似物抗性的營養缺陷型突變誘導過程及 L-色氨痠高產複閤突變菌株的篩選。方法採用硫痠二乙酯、紫外線、鈷60γ-射線等誘變方法交扠處理起始與突變菌株,通過營養缺陷錶型和自殺代謝底物抗性的篩選方法,定嚮突變和選育 L-色氨痠閤成與分解代謝突變的色氨痠高產菌株。結果通過多次連續營養缺陷型誘變選育,篩選齣一株具有分支痠-Trp/Phe/Tyr代謝途徑L-Phe和 L-Tyr 閤成缺陷型和 L-Trp 分解代謝自殺代謝底物抗性的 L-色氨痠高產菌 HX22-118(?Phe--?Tyr--5FTr-4FPr-SGr)；通過連續傳代10次髮酵,色氨痠產痠最高達到28.4 g/L,平均27.1 g/L,較齣髮菌株HX22產痠水平提高81.8%。結論選育齣的高產菌株具有多重代謝途徑突變(?Phe--?Tyr--5FTr-4FPr-SGr),突變體具有良好的遺傳穩定性,具有後續工業化生產應用潛力。
목적：이곡안산봉간균(Corynebacterium glutamicum)HX-22위출발균주,연구료목표발효산물L-색안산합성도경교차반궤억제도경대사돌변여색안산분해대사유사물항성적영양결함형돌변유도과정급 L-색안산고산복합돌변균주적사선。방법채용류산이을지、자외선、고60γ-사선등유변방법교차처리기시여돌변균주,통과영양결함표형화자살대사저물항성적사선방법,정향돌변화선육 L-색안산합성여분해대사돌변적색안산고산균주。결과통과다차련속영양결함형유변선육,사선출일주구유분지산-Trp/Phe/Tyr대사도경L-Phe화 L-Tyr 합성결함형화 L-Trp 분해대사자살대사저물항성적 L-색안산고산균 HX22-118(?Phe--?Tyr--5FTr-4FPr-SGr)；통과련속전대10차발효,색안산산산최고체도28.4 g/L,평균27.1 g/L,교출발균주HX22산산수평제고81.8%。결론선육출적고산균주구유다중대사도경돌변(?Phe--?Tyr--5FTr-4FPr-SGr),돌변체구유량호적유전은정성,구유후속공업화생산응용잠력。
Objective To research the breeding of high L-tryptophan yield with multiple synthetic and metabolic pathway mutation strain by using Corynebacterium glutamicum HX-22 as the starting strain. Methods Diethyl sulfate (DES), UV, and cobalt-60 gamma-ray mutagenesis method were performed cross processing starting on C. glutamicum HX-22 and mutant strain. The auxotrophic phenotype and metabolic suicide substrate resistance screening methods were used, and targeted mutagenesis and breeding of L-tryptophan acid synthesis and catabolism mutation of lubricious ammonia acid producing strain. Results Through continuous type defect mutagenesis breeding for many times, the strains with auxotroph and resistance marker of L-tryptophan high yield bacteria HX22-118 (?Phe--?Tyr--5FTr-4FPr-SGr) was screened, then extend the 10 times in succeeding transfer culture, the L-trp fermentation yield reached to 27.1 g/L, which was increased by 81.8% comparing to the wild start strain. Conclusion The selected multiple mutated strain HX22-118 (?Phe--?Tyr--5FTr-4FPr-SGr) with high L-trp yielding strain has a good genetic stability, which can be applied in industrial application.
