Protective Role of Bacterial Alkanesulfonate Monooxygenase under Oxidative Stress

Abstract

Bacterial alkane metabolism is associated with a number of cellular stresses, including membrane stress and oxidative stress, and the limited uptake of charged ions such as sulfate. In the present study, the genes ssuD and tauD in Acinetobacter oleivorans DR1 cells, which encode an alkanesulfonate monooxygenase and a taurine dioxygenase, respectively, were found to be responsible for hexadecanesulfonate (C16SO3H) and taurine metabolism, and Cbl was experimentally identified as a potential regulator of ssuD and tauD expression. The expression of ssuD and tauD occurred under sulfate-limited conditions generated during n-hexadecane degradation. Interestingly, expression analysis and knockout experiments suggested that both genes are required to protect cells against oxidative stress, including that generated by n-hexadecane degradation and H2O2 exposure. Measurable levels of intracellular hexadecanesulfonate were also produced during n-hexadecane degradation. Phylogenetic analysis suggested that ssuD and tauD are mainly present in soil-dwelling aerobes within the Betaproteobacteria and Gammaproteobacteria classes, which suggests that they function as controllers of the sulfur cycle and play a protective role against oxidative stress in sulfur-limited conditions. IMPORTANCE ssuD and tauD, which play a role in the degradation of organosulfonate, were expressed during n-hexadecane metabolism and oxidative stress conditions in A. oleivorans DR1. Our study confirmed that hexadecanesulfonate was accidentally generated during bacterial n-hexadecane degradation in sulfate-limited conditions. Removal of this by-product by SsuD and TauD must be necessary for bacterial survival under oxidative stress generated during n-hexadecane degradation.

Tobramycin Stress Induced Differential Gene Expression in Acinetobacter baumannii

“…tauD encodes taurine dioxygenase that is required for the utilization of taurine as a sulphur source. In A. oleivorans DR1, deletion of tauD exhibited increased sensitivity to H 2 O 2 , highlighting its protective role in oxidative stress [31]. cysD encodes a subunit of sulfate adenylyltransferase that catalyzes the first step in sulfate assimilation pathway.…”

Glutamate as an Efficient Amine Donor for the Synthesis of Chiral β‐ and γ‐Amino Acids Using Transaminase

“…TAs have increasingly been used in the synthesis of these chiral building blocks . TA‐mediated reductive amination of prochiral ketones to their corresponding amines, often suffers from inhibition of the enzyme by co‐product, and unfavorable thermodynamic equilibrium ,. Therefore, selection of the proficient amine donor is one of the most critical issues for the efficient TA‐reactions.…”

Osmotic stress tolerance and transcriptome analysis of Gluconobacter oxydans to extra-high titers of glucose

“…The effect of glucose titers on the intra-cellular ATP concentration of the G. oxydans. alkanesulfonate was transferred into the cell and oxidized by alkanesulfonate monooxygenase, resulting in the production of aldehyde and sulfite (Park et al, 2020). The sulfite generated by both pathways was reduced to sulfide by sulfite reductase and subsequently transferred onto O-acetylserine to yield cysteine.…”