Genome Property Definition Page

Accession

GenProp0290

Name

class II (B12-dependent) ribonucleotide reductase

Type

SYSTEM

Description

Ribonucleotide reductases (RNRs) are responsible for the conversion of the ribose sugar of RNA into the deoxyribose sugar of DNA. This is the rate-limiting step of DNA biosynthesis. The class II RNRs consist of a single subunit and generate the required radical via an adenosylcobalamin (B12) cofactor. The most common gene symbols for this gene is NrdJ, although the gene in mycobacterium is called NrdZ. The first characterized NrdJ gene, from Lactobacillus leichmannii, acted specifically on nucleoside triphosphates like the class III enzymes (1.17.4.2) and unlike the class I enzymes which act on the diphosphates (1.17.4.1). However, as further B12-dependent RNRs were characterized, it became clear that this is the exception rather than the rule. This property captures both types.

JCVI Role

2'-Deoxyribonucleotide metabolism

Parent Property

GenProp0284: cobalamin-utilizing enzymes
GenProp0287: ribonucleotide reduction

Literature References

[ 1 ]Lawrence CC, Stubbe J The function of adenosylcobalamin in the mechanism of ribonucleoside triphosphate reductase from Lactobacillus leichmannii. Curr Opin Chem Biol 1998 Oct;2(5):650-5. PMID 9818192

Gene Ontology Term

GO:0009265: 2'-deoxyribonucleotide biosynthetic process (biological_process)

Components

Step Name	Step Num	Required	Evidence (Method)	Evidence Go Terms
B12-dependent ribonucleotide reductase	NrdJ/Z	YES	TIGR02505 (HMM): ribonucleoside-triphosphate reductase, adenosylcobalamin-dependent TIGR02504 (HMM): ribonucleoside-diphosphate reductase, adenosylcobalamin-dependent	GO:0009265: 2'-deoxyribonucleotide biosynthetic process GO:0009265: 2'-deoxyribonucleotide biosynthetic process

Parent Properties

Accession	Name
GenProp0284	cobalamin-utilizing enzymes
GenProp0287	ribonucleotide reduction

Sibling Properties

Accession	Name
GenProp0288	tetrahydromethanopterin S-methyltransferase complex
GenProp0294	ethanolamine degradation proteinaceous organelle
GenProp0289	class I (aerobic) ribonucleotide reductase
GenProp0291	class III (anaerobic) ribonucleotide reductase