7oct

Publication Abstract from PubMed

SignificanceMannitol biosynthesis is essential for Acinetobacter baumannii to cope with osmotic stress. Currently, only Pseudomonas putida, Acinetobacter baylyi, and A. baumannii are able to de novo synthesize mannitol by a structurally unique bifunctional mannitol-1-phosphate dehydrogenase/phosphatase (AbMtlD). The molecular mechanism of reduction and dephosphorylation of fructose-6-phosphate to mannitol is highly dependent on the substrate shuffling from one protomer to the other protomer by a unique helix-loop-helix domain-mediated dimer formation, thus ensuring unidirectional and efficient biosynthesis of mannitol. These observations support an evolutionary adaptation of AbMtlD by fusion of dehydrogenase and phosphatase domains to facilitate efficient unidirectional enzymatic production of mannitol, unifying regulatory control and minimizing the intracellular concentration of toxic mannitol-1-phosphate during salt stress.

Unidirectional mannitol synthesis of Acinetobacter baumannii MtlD is facilitated by the helix-loop-helix-mediated dimer formation.,Tam HK, Konig P, Himpich S, Ngu ND, Abele R, Muller V, Pos KM Proc Natl Acad Sci U S A. 2022 Apr 5;119(14):e2107994119. doi:, 10.1073/pnas.2107994119. Epub 2022 Apr 1. PMID:35363566^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.