Isolation of a novel platform bacterium for lignin valorization and its application in glucose-free cis,cis-muconate production.

Microbial production of cis,cis-muconate (ccMA) from phenolic compounds obtained by chemical depolymerization of lignin is a promising approach to valorize lignin. Because microbial production requires a large amount of carbon and energy source, it is desirable to establish a ccMA-producing strain that utilizes lignin-derived phenols instead of general sources like glucose. We isolated Pseudomonas sp.

Structural and dynamic features of the MutT protein in the recognition of nucleotides with the mutagenic 8-oxoguanine base.

Escherichia coli MutT hydrolyzes 8-oxo-dGTP to 8-oxo-dGMP, an event that can prevent the misincorporation of 8-oxoguanine opposite adenine in DNA. Of the several enzymes that recognize 8-oxoguanine, MutT exhibits high substrate specificity for 8-oxoguanine nucleotides; however, the structural basis for this specificity is unknown. The crystal structures of MutT in the apo and holo forms and in the binary and ternary forms complexed with the product 8-oxo-dGMP and 8-oxo-dGMP plus Mn(2+), respectively, were determined.