CeBiTec Colloquium
Monday, June 15th 2015, 17 c.t.
G2-104, CeBiTec Building
Prof. Dr. Ok Bin Kim
Department of Life Science, School of Natural Sciences, Ewha Womans University (Korea)
C4-dicarboxylates transporters for anaerobic growth on fumarate in Actinobacillus succinogenes

Actinobacillus succinogenes that is known to produce large amounts of succinate during hexose fermentation was able to grow on C4-dicarboxylates like fumarate under aerobic and anaerobic condition. Succinate was the major product from anaerobic growth on fumarate, similar to growth on glucose.
Transport assay with 14C-fumarate and 14C-succinate revealed that A. succinogenes has several transport systems dependently on concentration of C4-dicarboxylates. Some of them required proton potential, but the others Na+ gradient.
Global transcriptome analysis showed that seven transport systems are expressed during anaerobic growth on fumarate, which includes transporters of the Dcu, DcuC, DASS, and TRAP family. The Dcu transporter 1999 exhibited extreme high transcription. Transport assay with the 1999-deletion-mutant demonstrated that the 1999 transporter played a major role in C4-dicarboxylate transport in mM range. Overall, A. succinogenes could utilize different protein systems for anaerobic C4-dicarboxylates transport, according to availability of driving force and substrate concentration.

Host: Prof. Dr. Volker Wendisch