REGULATED EXPRESSION OF THE NOR-1 AND VER-1 GENES ASSOCIATED WITH AFLATOXIN BIOSYNTHESIS
REGULATED EXPRESSION OF THE NOR-1 AND VER-1 GENES ASSOCIATED WITH AFLATOXIN BIOSYNTHESIS
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DOI：
10.1128/aem.59.5.1642-1646.1993
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发表时间：
1993-05-01
影响因子：
4.4
通讯作者：
LINZ, JE
中科院分区：
文献类型：
--
作者：
SKORY, CD;CHANG, PK;LINZ, JE
RNA转录积累的ver-1和nor-1基因，这是与黄曲霉毒素的生物合成在真菌寄生曲霉，测量之前和期间的黄曲霉毒素生产在液体振荡培养。直到接近营养期（生长期）结束时才检测到转录本，并且在支持黄曲霉毒素的生长培养基中分批发酵期间，仍可以观察到良好的稳定期。两个转录本的最大积累发生在静止期开始之前。黄曲霉毒素B在ver-1和nor-1转录物出现后约8小时首次检测到。与此相反，最大的转录积累的pyrG基因（编码乳清酸核苷单磷酸脱羧酶），这是参与初级代谢，观察到在开始的营养期时，不能检测到的ver-1和nor-1转录。还研究了从非黄曲霉毒素支持培养基（蛋白胨矿物盐[PMS]）向含葡萄糖培养基（葡萄糖矿物盐[GMS]）的营养转换后ver-1和nor-1转录物的蓄积，含葡萄糖培养基支持黄曲霉毒素生物合成。ver-1和nor-1的转录物在PMS培养基上不能检测到，但在转移到GMS培养基后约4至7小时确实积累。此外，在PMS培养基中未检测到黄曲霉毒素，但在从PMS转换为GMS后24小时内观察到黄曲霉毒素积累。这些数据表明，黄曲霉毒素的生物合成部分是由ver-1和nor-1转录本的积累调节。
RNA transcript accumulation for the ver-1 and nor-1 genes, which are associated with aflatoxin biosynthesis in the fungus Aspergillus parasiticus, was measured before and during aflatoxin production in liquid shake culture. Transcripts were not detected until near the end of trophophase (growth phase) and could still be observed well into stationary phase during batch fermentation in an aflatoxin-supporting growth medium. Maximum accumulation of both transcripts occurred just prior to the onset of stationary phase. Aflatoxin B, was first detected approximately 8 h after the appearance of the ver-1 and nor-1 transcripts. In contrast, maximum transcript accumulation for the pyrG gene (encoding orotidine monophosphate decarboxylase), which is involved in primary metabolism, was observed at the onset of trophophase when the ver-1 and nor-1 transcripts could not be detected. Accumulation of the ver-1 and nor-1 transcripts was also studied following a nutritional shift from a non-aflatoxin-supporting medium (peptone mineral salts [PMS]) to a glucose-containing medium (glucose mineral salts [GMS]), which does support aflatoxin biosynthesis. Transcripts from ver-1 and nor-1 could not be detected on PMS medium but did accumulate approximately 4 to 7 h following transfer to GMS medium. Additionally, aflatoxins were not detected in PMS medium but were observed to accumulate within 24 h after the shift from PMS to GMS. These data suggest that aflatoxin biosynthesis is in part regulated by the accumulation of the ver-1 and nor-1 transcripts.