Effects of putA and vgb Genes on trans-4-Hydroxy-L-Proline Production

Abstract:

Trans-4-hydroxy-L-proline is widely distributed in nature and applied in the pharmaceutical，chemical，food and cosmetic products. In order to interrupt the bacterial degradation of proline during the biosynthesis process of trans-4-hydroxy-L-proline，putA gene was deleted using Red/ET homologous recombination system. Wild types and mutants were cultured in GT and GC media，and the trans-4-hydroxy-L-proline yields were compared to obtain the optimal strain and medium. On the other hand，vgb gene was introduced into the cell and its effect on trans-4-hydroxy-L-proline production was studied. The results show that the knockout of putA gene can prevent the degradation of proline，and with an adequate supply of the carbon source，GC medium is better for producing trans-4-hydroxy-L-proline than GT medium. Moreover，all of the consumed proline can be transformed to trans-4-hydroxy-L-proline in putA deletion mutants. By contrast，the presence of vgb gene can significantly improve trans-4-hydroxy-L-proline production.