Transformation of the Pseudonocardiaceae amycolatopsis sp. strain HR167 is highly dependent on the physiological state of the cells.

摘要: The Pseudonocardiaceae Amycolatopsis sp. strain HR167 is used in a biotransformation process to produce vanillin from ferulic acid. To make this accessible for genetic engineering, direct mycelium transformation system developed mediterranei [Madon and Hutter (1991) J Bacteriol 173:6325–6331] was applied optimized HR167. physiological state of the cells had major influence on rate. highest rate about 7×105 transformants per microgram DNA obtained with harvested 6.5–7.5 h after culture has reached stationary growth phase. When were outside time slot, drastically decreased. density suspensions mixture methylation plasmid also crucial parameters. With isolated Escherichia coli ET12567, rates 3,500-fold higher than those E. XL1-Blue.