Pendyala L, Wellman A M
Biochim Biophys Acta. 1975 Apr 7;385(2):194-206. doi: 10.1016/0304-4165(75)90348-7.
Conidia of four adenine auxotrophs (ad 9, ad 3B, ad 8 and ad 4) of Neurospora crassa differ in their ability to germinate on adenine-deficient medium. A large percentage of the ad 9 and ad 3B mutant conidia germinate while those of ad 8 and ad 4 mutant do not. No correlation was found between the size of the conidial purine reserves and the conidial ability to germinate. In all the strains the major fraction of the conidial purine reserve pools was inosine. The ad 8 and ad 4 mutants are blocked after IMP formation in the adenine biosynthetic pathway and therefore cannot use the stored inosine for germination. Pool-utilization studies indicated that in all strains investigated some of the purine reserves were lost from the conidia during incubation. In the most readily germinating strain, ad 9, only small amounts of the purine pool were lost from the conidia and a large portion of the reserve pool was used for nucleic acid synthesis. The nature of the purine reserves present in the conidia, and the ability of the strains to prevent loss of the stored purines from the conidia appear to be among the factors influencing the conidial germination of the adenine mutants of N. crassa.
粗糙脉孢菌的四个腺嘌呤营养缺陷型（ad9、ad3B、ad8和ad4）的分生孢子在缺乏腺嘌呤的培养基上的萌发能力存在差异。ad9和ad3B突变型分生孢子中有很大比例能够萌发，而ad8和ad4突变型的分生孢子则不能。未发现分生孢子中嘌呤储备的量与分生孢子的萌发能力之间存在相关性。在所有菌株中，分生孢子嘌呤储备池的主要成分是次黄苷。ad8和ad4突变体在腺嘌呤生物合成途径中IMP形成后受阻，因此不能利用储存的次黄苷进行萌发。储备池利用研究表明，在所有研究的菌株中，一些嘌呤储备在培养过程中从分生孢子中流失。在最容易萌发的菌株ad9中，分生孢子中只有少量嘌呤储备流失，且储备池的很大一部分用于核酸合成。分生孢子中存在的嘌呤储备的性质，以及菌株防止储存的嘌呤从分生孢子中流失的能力，似乎是影响粗糙脉孢菌腺嘌呤突变体分生孢子萌发的因素之一。
