School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
Centre for Rural Development and Technology, IIT Delhi, New Delhi, India.
Bioresour Technol. 2021 Jun;330:124981. doi: 10.1016/j.biortech.2021.124981. Epub 2021 Mar 17.
Syringyl monomeric units are the most common intermediates encountered during hardwood lignin degradation. In the present study, efficient utilization of syringaldehyde (SAld), syringic acid (SAc) by Burkholderia sp. ISTR5 (R5) has been shown. The proteogenomic analysis of Burkholderia sp. ISTR5 was done to understand the enzymes involved in the degradation of syringaldehyde and syringic acid. Various proteins such as aldehyde dehydrogenase, laccase, and oxidoreductases were highly upregulated during growth on syringaldehyde and syringic acid. R5 completely transformed both the substrates SAld and SAc to other hydrocarbons in 48 h and 24 h, respectively. Moreover, bioconversion of syringyl lignins followed an unusual pathway and accumulated a considerable amount of industrially valuable chemical malic acid in the reaction titer. This study shows the robust chassis of R5 to cope with the aromatic aldehydic stress and simultaneous bioconversion into valuable products for an efficient biorefinery.
丁香醛单体是硬木木质素降解过程中最常见的中间体。本研究表明，伯克霍尔德氏菌（ISTR5）R5 能够有效利用丁香醛（SAld）和丁香酸（SAc）。对伯克霍尔德氏菌 ISTR5 的蛋白基因组学分析，以了解参与丁香醛和丁香酸降解的酶。在以丁香醛和丁香酸为生长基质时，醛脱氢酶、漆酶和氧化还原酶等各种蛋白高度上调。R5 能够在 48 小时和 24 小时内将两种基质 SAld 和 SAc 完全转化为其他碳氢化合物。此外，丁香基木质素的生物转化遵循一条不寻常的途径，并在反应产率中积累了相当数量的工业上有价值的化学物质马来酸。这项研究表明，R5 具有强大的底盘来应对芳香醛应激，并同时将其生物转化为高效生物炼制的有价值产品。
