Enhanced <span style="font-variant: small-caps">l</span>-Lysine into 1,5-Diaminopentane Conversion via Statistical Optimization of Whole-Cell Decarboxylation System

• Main Authors: Hanyong Kim, Hah Young Yoo, Nohseong Park, Haeun Kim, Jonghwa Lee, Yesol Baek, Taek Lee, Jong-Min Oh, Jaehoon Cho, Chulhwan Park
• Format: Article
• Language: English
• Published: MDPI AG 2019-08-01
• Series: Polymers
• Subjects: decarboxylation; 1,5-diaminopentane; <i>Hafnia alvei</i>; <span style="font-variant: small-caps">l</span>-lysine; statistical optimization
• Online Access: https://www.mdpi.com/2073-4360/11/8/1372

The global lysine companies in the feed industry have steadily built their production facilities due to the high demand for <span style="font-variant: small-caps;">l</span>-lysine in animal farms, and in recent years there have been excessive supply problems and the world market price of <span style="font-variant: small-caps;">l</span>-lysine has fallen. In this study, the conversion of 1,5-diaminopentane (DAP) by decarboxylation of <span style="font-variant: small-caps;">l</span>-lysine was strategically chosen to enhance the value of lysine. The decarboxylation is enzymatically accessible, and <i>Hafnia alvei</i>, which is the producer of <span style="font-variant: small-caps;">l</span>-lysine decarboxylase, was applied as a whole-cell form. In the designed whole-cell biocatalytic system, the major four reaction factors were selected by fundamental investigation and then statistical optimization was performed to estimate the optimum condition. The predicted conversion was assessed at about 94.6% at the optimum conditions (125.1 mM <span style="font-variant: small-caps;">l</span>-lysine and 71.5 g/L acetone concentration at 35.2 &#176;C for 8.4 h). Under the determined conditions, DAP conversions by using analytical, feed and industrial crude <span style="font-variant: small-caps;">l</span>-lysine were found to be 98.3%, 92.5% and 72.4%, respectively. These results could be suggested to solve the problem of excessive supplied lysine and also to provide guidance for improved enzymatic conversion by statistical optimization.