Regulation of the enzymes of lysine biosynthesis in Bacillus sphaericus NCTC 9602 during vegetative growth
Regulation of the enzymes of lysine biosynthesis in Bacillus sphaericus NCTC 9602 during vegetative growth
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球形芽孢杆菌 NCTC 9602 营养生长过程中赖氨酸生物合成酶的调节
DOI：
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发表时间：
1986
期刊：
影响因子：
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通讯作者：
P. White
中科院分区：
文献类型：
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作者：
Annie T. M. Bartlett;P. White
总结：在最小（乙酸盐加盐）培养基中，从分批培养物的指数期后期收获的球形芽孢杆菌提取物中测定酶。天冬氨酸激酶被苏氨酸阻遏和抑制;赖氨酸单独没有影响，但它增加了抑制（但不是阻遏）苏氨酸。天冬氨酸β-半醛脱氢酶被赖氨酸轻微抑制。二氢吡啶二羧酸合酶被赖氨酸非竞争性抑制，二氢吡啶二羧酸还原酶被赖氨酸部分抑制。二氨基庚二酸脱氢酶（以四氢吡啶二羧酸为底物）被内消旋二氨基庚二酸抑制。赖氨酸不抑制二氨基庚二酸脱羧酶，仅轻微抑制该酶。一个营养缺陷型突变体，需要苏氨酸和蛋氨酸排泄赖氨酸后，生长已停止与有限浓度的苏氨酸。
SUMMARY: Enzymes were assayed in extracts of Bacillus sphaericus harvested late in the exponential phase from batch cultures in a minimal (acetate plus salts) medium. Aspartokinase was repressed and inhibited by threonine; lysine alone had no effect, though it increased the inhibition (but not the repression) by threonine. Aspartic β-semialdehyde dehydrogenase was slightly repressed by lysine. Dihydrodipicolinate synthase was inhibited non-competitively by lysine, and dihydro-dipicolinate reductase was partly repressed by lysine. Diaminopimelate dehydrogenase (with tetrahydrodipicolinate as substrate) was inhibited by meso-diaminopimelate. Lysine did not repress diaminopimelate decarboxylase, and only slightly inhibited this enzyme. An auxotrophic mutant that required threonine and methionine excreted lysine after growth had stopped with a limited concentration of threonine.