PDBsum entry 4zd6

Lyase

PDB id: 4zd6

Contents

Protein chains

(+ 0 more) 225 a.a.

Ligands

MES

Metals

_CL ×6

_MG ×3

Waters ×1045

PDB id:

4zd6

Name:

Lyase

Title:

Halohydrin hydrogen-halide-lyase, hheb

Structure:

Halohydrin epoxidase b. Chain: a, b, c, d, e, f. Fragment: unp residues 11-235. Engineered: yes

Source:

Corynebacterium sp.. Organism_taxid: 1720. Gene: hheb. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

1.60Å R-factor: 0.177 R-free: 0.207

Authors:

F.Watanabe,F.Yu,A.Ohtaki,Y.Yamanaka,K.Noguchi,M.Yohda,M.Odaka

Key ref:

F.Watanabe et al. (2015). Crystal structures of halohydrin hydrogen-halide-lyases from Corynebacterium sp. N-1074. Proteins, 83, 2230-2239. PubMed id: 26422370 DOI: 10.1002/prot.24938

Date:

17-Apr-15 Release date: 04-Nov-15

Protein chains

Q46347  (Q46347_CORSP) -  Halohydrin epoxidase B from Corynebacterium sp

Seq: 235 a.a.

Struc: 225 a.a.

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1002/prot.24938

Proteins 83:2230-2239 (2015)

PubMed id: 26422370

Crystal structures of halohydrin hydrogen-halide-lyases from Corynebacterium sp. N-1074.

F.Watanabe, F.Yu, A.Ohtaki, Y.Yamanaka, K.Noguchi, M.Yohda, M.Odaka.

ABSTRACT

Halohydrin hydrogen-halide-lyase (H-Lyase) is a bacterial enzyme that is involved in the degradation of halohydrins. This enzyme catalyzes the intramolecular nucleophilic displacement of a halogen by a vicinal hydroxyl group in halohydrins to produce the corresponding epoxides. The epoxide products are subsequently hydrolyzed by an epoxide hydrolase, yielding the corresponding 1, 2-diol. Until now, six different H-Lyases have been studied. These H-Lyases are grouped into three subtypes (A, B, and C) based on amino acid sequence similarities and exhibit different enantioselectivity. Corynebacterium sp. strain N-1074 has two different isozymes of H-Lyase, HheA (A-type) and HheB (B-type). We have determined their crystal structures to elucidate the differences in enantioselectivity among them. All three groups share a similar structure, including catalytic sites. The lack of enantioselectivity of HheA seems to be due to the relatively wide size of the substrate tunnel compared to that of other H-Lyases. Among the B-type H-Lyases, HheB shows relatively high enantioselectivity compared to that of HheBGP1 . This difference seems to be due to amino acid replacements at the active site tunnel. The binding mode of 1, 3-dicyano-2-propanol at the catalytic site in the crystal structure of the HheB-DiCN complex suggests that the product should be (R)-epichlorohydrin, which agrees with the enantioselectivity of HheB. Comparison with the structure of HheC provides a clue for the difference in their enantioselectivity. Proteins 2015; 83:2230-2239. © 2015 Wiley Periodicals, Inc.