Wiebe Marilyn G, Blakebrough Margaret L, Craig Sally H, Robson Geoffrey D, Trinci Anthony P J
School of Biological Sciences, 1.800 Stopford Building, University of Manchester, Manchester, M13 9PT, UK.
Microbiology (Reading). 1996 Mar;142 ( Pt 3):525-532. doi: 10.1099/13500872-142-3-525.
Chlorate-resistant, highly branched (colonial) mutants and auxotrophic mutants were used to study the nuclear distribution, morphology and growth of heterokaryons of the Quorn myco-protein fungus, Fusarium graminearum A3/5. The results showed that for several complementary homokaryons, even a strong selective pressure was insufficient to maintain heterokaryons in a 'balanced' condition (i.e. exhibiting a wild-type or near wild-type phenotype). Furthermore, the margins of heterokaryotic colonies generally contained nuclei from only one of the parental homokaryons, indicating imperfect nuclear mixing within the mycelium. These observations suggest that recessive, colonial mutants may appear during Quorn myco-protein production following shear-induced separation of hyphal fragments which contain a sufficiently high ratio of colonial:wild-type nuclei for the colonial phenotype to be expressed.
利用抗氯酸盐、高度分支（菌落状）突变体和营养缺陷型突变体研究了曲霉菌蛋白真菌禾谷镰刀菌A3/5异核体的核分布、形态和生长。结果表明，对于几个互补的同核体，即使是很强的选择压力也不足以使异核体维持在“平衡”状态（即表现出野生型或接近野生型的表型）。此外，异核菌落的边缘通常只含有来自一个亲本同核体的细胞核，这表明菌丝体内的核混合不完全。这些观察结果表明，在曲霉菌蛋白生产过程中，当含有足够高比例的菌落状:野生型细胞核的菌丝片段因剪切而分离时，可能会出现隐性的菌落状突变体，从而使菌落状表型得以表达。
