1.9.6.1 malfunction a gene nap deletion mutant can no longer grow on methanol in contrast to the wild-type and shows almost abolished N2O production from nitrate -, 741478 1.9.6.1 physiological function a mutant strain defective for napA is not able to denitrify and grow on nitrate. The wild-type strain reaches 40 000 ppm of N2O emission and its growth is 10fold higher than that of the mutant strain. In the presence of nitrite as terminal electron acceptor, both wild-type and mutant are able to denitrify and to grow with no significant difference between both strains. NapA plays a role in Agrobacterium fabrum C58 fitness but is not involved in A. fabrum C58 root colonization -, 764679 1.9.6.1 metabolism cytochromes c encoded by genes in close proximity to the genes for XoxF proteins and methylamine dehydrogenase functions are likely involved in the metabolism with Nap, pathway overview -, 741478 1.9.6.1 physiological function Escherichia coli is a Gram-negative bacterium that can use nitrate during anaerobic respiration. The catalytic subunit of the involved periplasmic nitrate reductase NapA contains two types of redox cofactor and is exported across the cytoplasmic membrane by the twin-arginine protein transport pathway 742486 1.9.6.1 evolution genotyping of different strains from M and G populations, overview. The only mutated gene shared between the strains from populations M and G is bll4572, this gene is mutated in all six strains -, 742380 1.9.6.1 additional information modeling of regulation of nap and nos genes by NasST system in Bradyrhizobium japonicum strain USDA110 and nasS and Nos++ mutant strains -, 742380 1.9.6.1 physiological function napAB expression is required for anaerobic growth recovery by DELTAnarXL (a deletion encompassing the bulk of narXL) 711653 1.9.6.1 additional information NapD is a small cytoplasmic protein that is essential for the activity of the periplasmic nitrate reductase and binds tightly to the twinarginine signal peptide of NapA. NapA is structured in its unbound form. The NapA signal peptide undergoes conformational rearrangement upon interaction with NapD. NapA is at least partially folded when bound by its NapD partner. The NapD chaperone binds primarily at the NapA signal peptide in this system and points towards a role for NapD in the insertion of the molybdenum cofactor 742486 1.9.6.1 metabolism NasST regulates the nitrate-mediated response of nosZ and napE genes, from the dissimilatory denitrification pathway, regulation of nos and nap genes by the NasST system in the absence of nitrate in mutant strains, overview -, 742380 1.9.6.1 evolution periplasmic nitrate reductase (Nap) from Desulfovibrio desulfuricans and formate dehydrogenase (Fdh) from Escherichia coli K-12, both belonging to the DMSO reductase family, subfamily I, have a very similar structure, but very different activities. The show key differences that tune them for completely different functions in living cells. Both enzymes share almost identical three-dimensional protein foldings and active sites, in terms of coordination number, geometry and nature of the ligands. The substrates of both enzymes (nitrate and formate) are polyatomic anions that also share similar charge and stereochemistry. In terms of the catalytic mechanism, both enzymes have a common activation mechanism (the sulfur-shift mechanism) that ensures a constant coordination number around the metal ion during the catalytic cycle. In spite of these similarities, they catalyze very different reactions: Nap abstracts an oxygen atom from nitrate releasing nitrite, whereas FdH catalyzes a hydrogen atom transfer from formate and releases carbon dioxide. Detailed comparison, overview. A key difference between the catalytic mechanisms of Nap and FdH is the fact that only Mo is used to reduce nitrate but in Fdhs both Mo and W are catalytically competent to oxidize formate to carbon dioxide 741478