Nicotinate phosphoribosyltransferase pncB-type (IPR006405)

Short name: Nic_PRibTrfase_pncB

Overlapping homologous superfamilies

Family relationships


A deep split separates two related families of proteins, one of which includes experimentally characterised examples of nicotinate phosphoribosyltransferase (IPR006406), the first enzyme of NAD salvage biosynthesis. This entry represents the other family. Members have a different (longer) spacing of several key motifs and have an additional C-terminal domain of up to 100 residues. One argument suggesting that this family represents the same enzyme is that no species has a member of both families. Another is that the gene encoding this protein is located near other NAD salvage biosynthesis genes in Nostoc and in at least four different Gram-positive bacteria. NAD and NADP are ubiquitous in life. Most members of this family are from Gram-positive bacteria. An additional set of mutually closely related archaeal sequences score between the trusted and noise cut-offs.

This entry includes pncB1 and pncB2 from Mycobacterium tuberculosis, which also play a role in NAD salvage synthesis [PMID: 18490451].

GO terms

Biological Process

GO:0009435 NAD biosynthetic process

Molecular Function

GO:0004516 nicotinate phosphoribosyltransferase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.