Liang Bin, Du Xinjun, Li Ping, Sun Chanchan, Wang Shuo
Key Laboratory of Food Nutrition and Safety (Tianjin University of Science & Technology) , Ministry of Education , Tianjin 300457 , China.
J Agric Food Chem. 2018 Apr 25;66(16):4129-4138. doi: 10.1021/acs.jafc.8b00661. Epub 2018 Apr 13.
Monascus pigments (Mps) have been used as food colorants for several centuries in Asian countries. MptriA is a putative acetyltransferase gene involved in the MPs biosynthesis. To analyze the function of MptriA, an MptriA disruption strain (Δ MptriA) and a complementation strain (Δ MptriA:: MptriA) were successfully obtained In addition to the loss of color, the disruption of MptriA had little effect on the phenotypes during growth on four different media. The Δ MptriA strain showed decreased pigment and citrinin production during the liquid-fermentation process. Transcriptional analysis showed that the expression of several genes involved in the synthesis of pigments and citrinin was down-regulated in Δ MptriA. These results demonstrated that the role of MptriA was to transfer an acyl group to the pyranoquinone structure of the polyketide chromophore during Monascus pigment biosynthesis and to influence the citrinin biosynthesis pathway. This study contributes to the exploration of pigment biosynthesis in M. purpureus.
在亚洲国家，红曲色素（Mps）作为食品着色剂已使用了几个世纪。MptriA是一个推定的参与红曲色素生物合成的乙酰转移酶基因。为了分析MptriA的功能，成功获得了一个MptriA缺失菌株（ΔMptriA）和一个互补菌株（ΔMptriA::MptriA）。除了颜色丧失外，MptriA的缺失对在四种不同培养基上生长期间的表型影响很小。ΔMptriA菌株在液体发酵过程中色素和桔霉素产量降低。转录分析表明，在ΔMptriA中，几个参与色素和桔霉素合成的基因的表达下调。这些结果表明，MptriA的作用是在红曲色素生物合成过程中将一个酰基转移到聚酮发色团的吡喃醌结构上，并影响桔霉素生物合成途径。本研究有助于探索紫红红曲菌中色素的生物合成。
