Inhibition of Rhizomucor miehei and Candida rugosa lipases by d-glucose in esterification between l-alanine and d-glucose
详细信息 查看全文
- 作者：Bhandya R. ; Somashekar<sup>asup> ; Kenchaiah ; Lohith<sup>asup> ; Balaraman ; Manohar<sup>bsup> ; Soundar ; Divakar<sup>asup><sup> ; ; sup><sup>divakar643@gmail.comsup>
- 关键词：<span style=""font-variant ; small-caps"">lspan>-alanyl-<span style=""font-variant ; small-caps"">dspan>-glucose ; Candida rugosa lipase ; Rhizomucor miehei lipase ; Ping-Pong Bi-Bi mechanism ; competitive <span style=""font-variant ; small-caps"">d<
- 刊名：Journal of Bioscience and Bioengineering
- 出版年：2007
- 出版时间：February 2007
- 年：2007
- 卷：103
- 期：2
- 页码：122-128
- 全文大小：537 K
文摘
A detailed kinetic study of the esterification of d-glucose with l-alanine catalyzed by lipases from s="""">Rhizomucor miehei (RML) and s="""">Candida rugosa (CRL) showed that both lipases follow the Ping-Pong Bi-Bi mechanism, in which l-alanine and d-glucose bind in subsequent steps releasing water and l-alanyl-d-glucose, with competitive substrate inhibition by d-glucose at higher concentrations leading to the formation of dead-end lipase¡¤d-glucose complexes. An attempt to obtain the best fit of this kinetic model through curve fitting yielded good approximates of the apparent values of four important kinetic parameters: for RML-s="""">k<sub xmlns="""">catsub>=0.29¡À0.028¡Á10<sup xmlns="""">?sup> M h<sup xmlns="""">?sup> mg<sup xmlns="""">?sup>, s="""">K<sub xmlns="""">m l-alaninesub>= 4.9¡À0.51¡Á10<sup xmlns="""">?sup> M, s="""">K<sub xmlns="""">m d-glucosesub>=0.21¡À0.018¡Á10<sup xmlns="""">?sup> M, and s="""">K<sub xmlns="""">i d-glucosesub>=1.76¡À0.19¡Á10<sup xmlns="""">?sup> M; for CRL-s="""">k<sub xmlns="""">catsub>= 0.75¡À0.08¡Á10<sup xmlns="""">?sup> M h<sup xmlns="""">?sup> mg<sup xmlns="""">?sup>, s="""">K<sub xmlns="""">m l-alaninesub>=56.2¡À5.7¡Á10<sup xmlns="""">?sup> M, s="""">K<sub xmlns="""">m d-glucosesub>=16.2¡À1.8¡Á10<sup xmlns="""">?sup> M, and s="""">K<sub xmlns="""">i d-glucosesub> =21.0¡À1.9¡Á10<sup xmlns="""">?sup> M.