Tetrahydrofolate (THF) polyglutamates are a family of cofactors that carry and chemically activate one-carbon units for biosynthesis. THF-mediated one-carbon metabolism is a metabolic network of interdependent biosynthetic pathways that is compartmentalized in the cytoplasm, mitochondria, and nucleus. One-carbon metabolism in the cytoplasm is required for the synthesis of purines and thymidylate and the remethylation of homocysteine to methionine. One-carbon metabolism in the mitochondria is required for the synthesis of formylated methionyl-tRNA; the catabolism of choline, purines, and histidine; and the interconversion of serine and glycine. Mitochondria are also the primary source of one-carbon units for cytoplasmic metabolism. Increasing evidence indicates that folate-dependent de novo thymidylate biosynthesis occurs in the nucleus of certain cell types. Disruption of folate-mediated one-carbon metabolism is associated with many pathologies and developmental anomalies, yet the biochemical mechanisms and causal metabolic pathways responsible for the initiation and/or progression of folate-associated pathologies have yet to be established. This chapter focuses on our current understanding of mammalian folate-mediated one-carbon metabolism, its cellular compartmentation, and knowledge gaps that limit our understanding of one-carbon metabolism and its regulation.

Folate-mediated one-carbon metabolism.

Purine and pyrimidine nucleotide metabolism in higher plants.

Crystal structure of decameric 2-Cys peroxiredoxin from human erythrocytes at 1.7Å resolution

Background Human gut bacteria can synthesize proteinogenic amino acids and produce a range of metabolites via protein fermentation, some known to exert beneficial or harmful physiological effects on the host. However, the effects of the type and amount of dietary protein consumed on these metabolic processes, as well as the effects of the microbiota-derived amino acids and related metabolites on the host health are still predominantly unknown. Scope and approach This review provides an up-to-date description of the dominant pathways/genes involved in amino acid metabolism in gut bacteria, and provides an inventory of metabolic intermediates derived from bacterial protein fermentation that may affect human health. Advances in understanding bacterial protein fermentation pathways and metabolites generated at a global level via the implementation of ‘omics’ technologies are reviewed. Finally, the impact of dietary protein intake and high-protein diets on human health is discussed. Key findings and conclusions The intestinal microbiota is able to synthesize amino acids, but the net result of amino acid production and utilization, according to dietary patterns still needs to be determined. The amount of ingested dietary protein appears to modify both the diversity and composition of the intestinal microbiota as well as the luminal environment of the intestinal epithelium and peripheral tissues. The understanding of the consequences of such changes on the host physiology and pathophysiology is still in an early stage but major progress is expected in the near future with the investigation of host-microbe omics profiles from well-controlled human intervention studies.

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Gut microbiota role in dietary protein metabolism and health-related outcomes: The two sides of the coin

Serine hydroxymethyltransferase revisited.

Crystal structure of binary and ternary complexes of serine hydroxymethyltransferase from Bacillus stearothermophilus: insights into the catalytic mechanism.

Plant aspartate transcarbamylase: An affinity chromatographic method for the purification of the enzyme from germinated seedlings

CsHaN205, PL a = 6.438 (2), b = 7.486 (3), c = 8.048 (4)A, a = 72.2(1), fl = 80.8(1), y = 76.4 (1) °, D m = 1.65 (1) (flotation), D c = 1.64 Mg m -3, Z = 2. Final R = 0.095 for 1205 observed reflections. The molecule assumes the sterically least favourable conformation with the side chain carboxyl group staggered between the a-carboxyl group and the
N atom attached to C '~. The ureido group takes part in two specific interactions involving two nearly parallel hydrogen bonds in one and two convergent hydrogen bonds in the other.

http://journals.iucr.org/b/issues/1982/05/00/a21261/a21261.pdf

G.S. Jagannatha Rao

Papers

Crystal structure of binary and ternary complexes of serine hydroxymethyltransferase from Bacillus stearothermophilus: insights into the catalytic mechanism.

Plant aspartate transcarbamylase: An affinity chromatographic method for the purification of the enzyme from germinated seedlings

N-Carbamoyl-dl-aspartic acid