Wang Yi, Zhou Xu, Hur Jae-Seoun, Wang Juan
Wei Sheng Wu Xue Bao. 2014 Jul 4;54(7):770-7.
To isolate polyketide synthase (PKS) gene from medicinal Usnea longissima lichen forming fungi, and identify the function of obtained PKS.
We used Usnea. longissima lichen forming fungi to isolate PKS gene by nested PCR using degenerate primers and screening a Fosimid genomic library. MEGA 4.0.2 program was used for phylogenetic analysis and RT-PCR was used to detect gene expression.
We obtained a gene cluster including non-reducing PKS (UlPKS5), putative beta-lactamase and putative dehydratase from Usnea longissima lichen forming fungi. UlPKS5 contained ketosynthase (KS), acyl transferase (AT), product template (PT) and acyl carrier protein (ACP) domain. Phylogenetic analysis shows that UlPKS5 belonged to non-reducing PKS group V, which involved anthraquinone biosynthesis. RT-PCR analyses reveal that the expression of UlPKS5 was up-regulated by sucrose (2% and 10%) and sorbitol (10%).
PKS(UlPKS5), putative beta-lactamase and putative dehydratase were related with anthraquinone biosynthesis in U. longissima.
从药用长松萝地衣形成真菌中分离聚酮合酶（PKS）基因，并鉴定所获得PKS的功能。
我们利用长松萝地衣形成真菌，通过使用简并引物的巢式PCR和筛选Fosimid基因组文库来分离PKS基因。使用MEGA 4.0.2程序进行系统发育分析，并使用RT-PCR检测基因表达。
我们从长松萝地衣形成真菌中获得了一个基因簇，包括非还原型PKS（UlPKS5）、假定的β-内酰胺酶和假定的脱水酶。UlPKS5包含酮合成酶（KS）、酰基转移酶（AT）、产物模板（PT）和酰基载体蛋白（ACP）结构域。系统发育分析表明，UlPKS5属于非还原型PKS第五组，参与蒽醌生物合成。RT-PCR分析显示，UlPKS5的表达在蔗糖（2%和10%）和山梨醇（10%）作用下上调。
PKS（UlPKS5）、假定的β-内酰胺酶和假定的脱水酶与长松萝中蒽醌生物合成有关。
