Formate is the hydrogen donor for the anaerobic ribonucleotide reductase from Escherichia coli.

During anaerobic growth Escherichia coli uses a specific ribonucleoside-triphosphate reductase (class III enzyme) for the production of deoxyribonucleoside triphosphates. In its active form, the enzyme contains an iron-sulfur center and an oxygen-sensitive glycyl radical (Gly-681). The radical is generated in the inactive protein from S-adenosylmethionine by an auxiliary enzyme system present in E. coli. By modification of the previous purification procedure, we now prepared a glycyl radical-containing reductase, active in the absence of the auxiliary reducing enzyme system. This reductase uses formate as hydrogen donor in the reaction. During catalysis, formate is stoichiometrically oxidized to CO2, and isotope from [3H]formate appears in water. Thus E. coli uses completely different hydrogen donors for the reduction of ribonucleotides during anaerobic and aerobic growth. The aerobic class I reductase employs redox-active thiols from thioredoxin or glutaredoxin to this purpose. The present results strengthen speculations that class III enzymes arose early during the evolution of DNA.

A cyclophilin from the polycentric anaerobic rumen fungus Orpinomyces sp. strain PC-2 is highly homologous to vertebrate cyclophilin B.

A cyclophilin (CyP) purified to homogeneity from the polycentric anaerobic rumen fungus Orpinomyces sp. strain PC-2 had a molecular mass of 20.5 kDa and a pI of 8.1. The protein catalyzed the isomerization of the prolyl peptide bond of N-succinyl-Ala-Ala-(cis,trans)-Pro-Phe p-nitroanilide with a kcat/Km value of 9.3 x 10(6) M-1.s-1 at 10 degrees C and pH 7.8. Cyclosporin A strongly inhibited this peptidylprolyl cis-trans isomerase activity with an IC50 of 19.6 nM. The sequence of the first 30 N-terminal amino acids of this CyP had high homology with the N-terminal sequences of other eukaryotic CyPs. By use of a DNA hybridization probe amplified by PCR with degenerate oligonucleotide primers designed based on the amino acid sequences of the N terminus of this CyP and highly conserved internal regions of other CyPs, a full-length cDNA clone was isolated. It possessed an open reading frame encoding a polypeptide of 203 amino acids with a calculated molecular weight of 21,969, containing a putative hydrophobic signal peptide sequence of 22 amino acids preceding the N terminus of the mature enzyme and a C-terminal sequence, Lys-Ala-Glu-Leu, characteristic of an endoplasmic reticulum retention signal. The Orpinomyces PC-2 CyP is a typical type B CyP. The amino acid sequence of the Orpinomyces CyP exhibits striking degrees of identity with the corresponding human (70%), bovine (69%), mouse (68%), chicken (66%), maize (61%), and yeast (54%) proteins. Phylogenetic analysis based on the CyP sequences indicated that the evolutionary origin of the Orpinomyces CyP was closely related with CyPs of animals.

Control of odors from anaerobic lagoons treating food processing waste-waters /

Issued July 1978.

Mechanisms that regulate the intensity of oxidation-reduction in anaerobic sediments and natural water systems : final report /

"August 1978."

The effects of alcohol upon digestion in the stomach,

Thesis statement on label affixed to inside front cover.

Sulfuric acid digestion of leached zone /

Work performed at the International Minerals and Chemical Corporation under Contract AT(49-1)-545 with the U.S. Atomic Energy Commission.

Nitric acid digestion of leached zone /

"Contract No. AT(49-1)-538."

The anaerobic attached film expanded bed reactor for the treatment of dilute organic wastes /

Photocopy of typescript.

Digestion trial with two Jersey cows on full ration and on maintenance /

Mode of access: Internet.

De la digestion et des maladies de l'estomac : suivant le systeme de la trituration & du broyement, sans l'aide des levains ou de la fermentation, dont on fait voir l'impossibilité en santé & en maladie /

Mode of access: Internet.

De la digestion et des maladies de l'estomac : suivant le systeme de la trituration & du broyement, sans l'aide des levains ou de la fermentation, dont on fait voir l'impossibilité en santé & en maladie /

Tome premier, qui contient un discours préliminaire sur la trituration, une réponse à M. Silva, & cinq lettres, sur la révulsion, la saignée, le kermes mineral, & les maladies des yeux. -- Tome second, oú l'on a joint à la fin une dissertation de l'auteur de ce traité, sur la digestion des alimens, & une thèse latine du même, sur la production des maladies par le dérangement de la trituration.

De la digestion et des maladies de l'estomac : suivant le systeme de la trituration & du broyement, sans l'aide des levains ou de la fermentation, dont on fait voir l'impossibilité en santé & en maladie /

Tome premier, qui contient un discours préliminaire sur la trituration, une réponse à M. Silva, & cinq lettres, sur la révulsion, la saignée, le kermes mineral, & les maladies des yeux. -- Tome second, oú l'on a joint à la fin une dissertation de l'auteur de ce traité, sur la digestion des alimens, & une thèse latine du même, sur la production des maladies par le dérangement de la trituration.

De la Digestion, et des phénomènes qui se succèdent dans les organes digestifs pendant l'acte de l'assimilation ou de la nutrition, réponse à la question proposée par l'Institut Royal de France... /

Mode of access: Internet.