Zacchi L, Burla G, Zuolong D, Harvey P J
School of Chemical and Life Sciences, University of Greenwich, Wellington Street, London, UK.
J Biotechnol. 2000 Mar 10;78(2):185-92. doi: 10.1016/s0168-1656(00)00209-1.
Production of the extracellular heme protein lignin peroxidase (LiP) by Phanerochaete chrysosporium is currently associated with a number of requirements, namely exposure of the cultures to oxygen; limiting nutrient nitrogen or carbon and static or semi-static culture conditions. To obtain LiP activity in continuously agitated liquid culture requires the inclusion of a surfactant. However, using cellulose as the carbon source, we obtained high titres (0.2-0.4 U ml(-1)) of LiP in submerged liquid cultures under conditions of continuous agitation, without substrate limitation or the need to add oxygen or surfactant. Comparison of the morphological and physiological traits of hyphae maintained on either cellulose or free glucose supports observations that the synthesis of extracellular polysaccharide in the cultures grown on glucose, restricts oxygen diffusion into the hyphae, which is necessary for LiP induction. They also suggest that isozymes of LiP synthesised under these conditions may be triggered in response to oxidant stress.
黄孢原毛平革菌产生细胞外血红素蛋白木质素过氧化物酶（LiP）目前与一些条件相关，即培养物暴露于氧气；限制营养物质氮或碳以及静态或半静态培养条件。要在持续搅拌的液体培养物中获得LiP活性需要加入表面活性剂。然而，以纤维素作为碳源，我们在持续搅拌条件下的深层液体培养物中获得了高滴度（0.2 - 0.4 U ml⁻¹）的LiP，无需底物限制，也无需添加氧气或表面活性剂。对在纤维素或游离葡萄糖上生长的菌丝的形态和生理特征进行比较，支持了这样的观察结果：在以葡萄糖为碳源生长的培养物中，细胞外多糖的合成限制了氧气向菌丝内的扩散，而这是诱导LiP所必需的。这些结果还表明，在这些条件下合成的LiP同工酶可能是对氧化应激的响应而被触发。
