BACKGROUND L-Arginine is an important precursor of nitric oxide (NO) and protein synthesis. Arginine is produced in the body (mainly kidney) by de novo production from citrulline and by protein breakdown. Arginine availability appears to be limited in sepsis. OBJECTIVE The objective was to compare arginine and citrulline metabolism in septic patients and nonseptic control patients in an inten...

BACKGROUND Nitric oxide synthase (NOS) is an enzyme catalysing the conversion of L-arginine to L-citrulline and nitric oxide (NO), the latter being an essential messenger molecule for a range of biological processes. Whilst its role in higher vertebrates is well understood little is known about the role of this enzyme in early metazoan groups. For instance, NOS-mediated signalling has been asso...

The energy-generating pathways of Mycoplasma spp. are diverse. Thus, it was predicted that the ability of inhibitors of these pathways to block growth would vary among species. This prediction was tested with 14 Mycoplasma species and potential inhibitors. The greatest differentiation among test species was obtained using fluoride, iodoacetate (IAA), beta-fluoropyruvate (FP), cibacron blue (CB)...

In type 2 diabetes (T2D) macrophage dysfunction increases susceptibility to infection and mortality. This may result from the associated decreased plasma concentration of arginine, an amino acid that plays an important role in immunity. In vitro, increasing arginine availability leads to an improvement in macrophage function; however, arginine supplementation in diabetic obese patients may be d...

In the oxygenase domain of mouse inducible nitric-oxide synthase (iNOSoxy), a conserved tryptophan residue, Trp-457, regulates the kinetics and extent of l-Arg oxidation to N(omega)-hydroxy-l-arginine (NOHA) by controlling electron transfer between bound (6R)-tetrahydrobiopterin (H(4)B) cofactor and the enzyme heme Fe(II)O(2) intermediate (Wang, Z. Q., Wei, C. C., Ghosh, S., Meade, A. L., Heman...

Agmatine, decarboxylated arginine, is a metabolic product of mammalian cells. Considering the close structural similarity between L-arginine and agmatine, we investigated the interaction of agmatine and nitric oxide synthases (NOSs), which use L-arginine to generate nitric oxide (NO) and citrulline. Brain, macrophages and endothelial cells were respectively used as sources for NOS isoforms I, I...

In the tumor microenvironment, arginine is metabolized by arginase-expressing myeloid cells. This arginine depletion profoundly inhibits T cell functions and is crucially involved in tumor-induced immunosuppression. Reconstitution of adaptive immune functions in the context of arginase-mediated tumor immune escape is a promising therapeutic strategy to boost the immunological antitumor response...

Toward the creation of a robust and efficient producer of L-arginine and L-citrulline (arginine/citrulline), we have performed reengineering of a Corynebacterium glutamicum strain by using genetic information of three classical producers. Sequence analysis of their arg operons identified three point mutations (argR123, argG92(up), and argG45) in one producer and one point mutation (argB26 or ar...