Arst H N
Mol Gen Genet. 1978 Jul 6;163(1):23-7. doi: 10.1007/BF00268960.
Three unlinked genes where mutation can lead to D(+)-pantothenic acid auxotrophy in Aspergillus nidulans have been identified. pantoA is probably the structural gene for pantothenate synthetase (EC 6.3.2.1) whilst pantoB and pantoC are involved in the syntheses of D-pantoic acid and beta-alanine, respectively. A pantoC- mutant is tentatively considered to be blocked in conversion of 5,6-dihydrouracil to beta-ureidopropionate. An alternative route of beta-alanine biosynthesis occurs by the transamination of malonic semialdehyde, catalysed by GABA transaminase. The possibility that beta-alanine can be replaced by certain structurally related compounds and yet nevertheless yield biologically active coenzyme A analogues is discussed.
已鉴定出三个不连锁的基因，在构巢曲霉中，这些基因发生突变会导致对D（+）-泛酸营养缺陷。pantoA可能是泛酸合成酶（EC 6.3.2.1）的结构基因，而pantoB和pantoC分别参与D-泛解酸和β-丙氨酸的合成。一个pantoC-突变体暂被认为在5,6-二氢尿嘧啶转化为β-脲基丙酸的过程中受阻。β-丙氨酸生物合成的另一条途径是由GABA转氨酶催化丙二酸半醛的转氨作用。文中讨论了β-丙氨酸可被某些结构相关化合物替代但仍能产生生物活性辅酶A类似物的可能性。
