Journal of Biotechnology & Biomaterials
Open Access

Research Article

Genetic Engineering and Improvement of a Zymomonas mobilis for Arabinose Utilization and Its Performance on Pretreated Corn Stover Hydrolyzate

National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401, USA

Corresponding Author:

Yat-Chen Chou
National Bioenergy Center
National Renewable Energy Laboratory
15013 Denver West Parkway Golden, CO 80401,USA
Tel: 3033847766
E-mail: yat.chen.chou@nrel.gov

Received date:: March 18, 2015; Accepted date:: April 21, 2015; Published date:: April 28, 2015

Citation: Chou YC, Linger J, Yang S, Zhang M (2015) Genetic Engineering and Improvement of a Zymomonas mobilis for Arabinose Utilization and Its Performance on Pretreated Corn Stover Hydrolyzate. J Biotechnol Biomater 5:179. doi:https://dx.doi.org/10.4172/biotechnology-biomaterials.1000179

Copyright: © 2015 Chou YC, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

A glucose, xylose and arabinose utilizing Zymomonas mobilis strain was constructed by incorporating arabinose catabolic pathway genes, araBAD encoding L-ribulokinase, L-arabinose isomerase and L-ribulose-5-phosphate- 4-epimerase in a glucose, xylose co-fermenting host, 8b, using a transposition integration approach. Further improvement on this arabinose-capable integrant, 33C was achieved by applying a second transposition to create a genomic knockout (KO) mutant library. Using arabinose as a sole carbon source and a selection pressure, the KO library was subjected to a growth-enrichment process involving continuous sub-culturing for over 120 generations. Strain 13-1-17, isolated from such process demonstrated significant improvement in metabolizing arabinose in a dilute acid pretreated, saccharified corn stover slurry. Through Next Generation Sequencing (NGS) analysis, integration sites of the transposons were identified. Furthermore, multiple additional point mutations (SNPs: Single Nucleotide Polymorphisms) were discovered in 13-1-17, affecting genes araB and RpiB in the genome. We speculate that these mutations may have impacted the expression of the enzymes coded by these genes, ribulokinase and Ribose 5-P-isomerase, thus attributing to the improvement of the arabinose utilization.

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