Top Institute Food & Nutrition, P.O. Box 557, 6700 AN Wageningen, The Netherlands.
Fungal Biol. 2010 Feb-Mar;114(2-3):135-43. doi: 10.1016/j.mycres.2009.08.007.
The fhbA genes encoding putative flavohemoglobins (FHb) from Aspergillus niger and Aspergillus oryzae were isolated. Comparison of the deduced amino acid sequence of the A. niger fhbA gene and other putative filamentous fungal FHb-encoding genes to that of Ralstonia eutropha shows an overall conserved gene structure and completely conserved catalytic amino acids. Several yeasts and filamentous fungi, including both Aspergillus species have been found to contain a small FHb gene family mostly consisting of two family members. Based on these sequences the evolutionary history of the fungal FHb family was reconstructed. The isolated fhbA genes from A. oryzae and A. niger belong to a phylogenetic group, which exclusively contains Aspergillus genes. Different experimental approaches show that fhbA transcript levels appear during active hyphal growth. Moreover, in a pclA-disrupted strain with a hyperbranching growth phenotype, the transcript levels of the fhbA gene were 2–5 times higher compared to the wild-type. These results suggest that FHb from filamentous fungi have a function that is correlated to the hyphal growth phenotype.
从黑曲霉和米曲霉中分离到编码假定黄素血红蛋白（FHb）的 fhbA 基因。比较黑曲霉 fhbA 基因和其他丝状真菌 FHb 编码基因与 Ralstonia eutropha 的推导氨基酸序列表明，基因结构总体保守，催化氨基酸完全保守。已经发现包括两种曲霉在内的几种酵母和丝状真菌含有一个由两个家族成员组成的小 FHb 基因家族。基于这些序列，重建了真菌 FHb 家族的进化历史。从米曲霉和黑曲霉中分离到的 fhbA 基因属于一个专门包含曲霉基因的系统发育群。不同的实验方法表明，fhbA 转录本水平在活跃的菌丝生长过程中出现。此外，在具有超分枝生长表型的 pclA 缺失菌株中，fhbA 基因的转录本水平比野生型高 2-5 倍。这些结果表明，丝状真菌的 FHb 具有与菌丝生长表型相关的功能。
