The domain within your query sequence starts at position 96 and ends at position 148; the E-value for the HMG-CoA_red domain shown below is 2.8e-17.

QMLGVQGACKDNPGENARQLARIVCGTVMAGELSLMAALAAGHLVRSHMVHNR

HMG-CoA_red

HMG-CoA_red
PFAM accession number:PF00368
Interpro abstract (IPR002202):

There are two distinct classes of hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase enzymes: class I consists of eukaryotic and most archaeal enzymes ( EC 1.1.1.34 ), while class II consists of prokaryotic enzymes ( EC 1.1.1.88 ) [ (PUBMED:10068515) (PUBMED:15535874) ].

Class I HMG-CoA reductases catalyse the NADP-dependent synthesis of mevalonate from 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA). In vertebrates, membrane-bound HMG-CoA reductase is the rate-limiting enzyme in the biosynthesis of cholesterol and other isoprenoids. In plants, mevalonate is the precursor of all isoprenoid compounds [ (PUBMED:15535874) ]. The reduction of HMG-CoA to mevalonate is regulated by feedback inhibition by sterols and non-sterol metabolites derived from mevalonate, including cholesterol. In archaea, HMG-CoA reductase is a cytoplasmic enzyme involved in the biosynthesis of the isoprenoids side chains of lipids [ (PUBMED:10600463) ]. Class I HMG-CoA reductases consist of an N-terminal membrane domain (lacking in archaeal enzymes), and a C-terminal catalytic region. The catalytic region can be subdivided into three domains: an N-domain (N-terminal), a large L-domain, and a small S-domain (inserted within the L-domain). The L-domain binds the substrate, while the S-domain binds NADP.

Class II HMG-CoA reductases catalyse the reverse reaction of class I enzymes, namely the NAD-dependent synthesis of HMG-CoA from mevalonate and CoA [ (PUBMED:15028676) ]. Some bacteria, such as Pseudomonas mevalonii, can use mevalonate as the sole carbon source. Class II enzymes lack a membrane domain. Their catalytic region is structurally related to that of class I enzymes, but it consists of only two domains: a large L-domain and a small S-domain (inserted within the L-domain). As with class I enzymes, the L-domain binds substrate, but the S-domain binds NAD (instead of NADP in class I).

GO process:coenzyme A metabolic process (GO:0015936), oxidation-reduction process (GO:0055114)
GO function:hydroxymethylglutaryl-CoA reductase (NADPH) activity (GO:0004420)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry HMG-CoA_red