4BIF

Biochemical and structural characterisation of a novel manganese- dependent hydroxynitrile lyase from bacteria

Summary for 4BIF

• Entry DOI: 10.2210/pdb4bif/pdb
• Descriptor: CUPIN 2 CONSERVED BARREL DOMAIN PROTEIN, MANGANESE (II) ION (3 entities in total)
• Functional Keywords: lyase, metal-dependent, mandelonitrile, site-directed mutagenesis
• Biological source: GRANULICELLA TUNDRICOLA
• Total number of polymer chains: 8
• Total formula weight: 139401.58

Authors

Hajnal, I.,Lyskowski, A.,Hanefeld, U.,Gruber, K.,Schwab, H.,Steiner, K. (deposition date: 2013-04-10, release date: 2013-09-11, Last modification date: 2023-12-20)

Primary citation

Hajnal, I.,Lyskowski, A.,Hanefeld, U.,Gruber, K.,Schwab, H.,Steiner, K.
Biochemical and Structural Characterisation of a Novel Bacterial Manganese-Dependent Hydroxynitrile Lyase.
FEBS J., 280:5815-, 2013

PubMed Abstract: Hydroxynitrile lyases (HNLs), which catalyse the decomposition of cyanohydrins, are found mainly in plants. In vitro, they are able to catalyse the synthesis of enantiopure cyanohydrins, which are versatile building blocks in the chemical industry. Recently, HNLs have also been discovered in bacteria. Here, we report on the detailed biochemical and structural characterization of a hydroxynitrile lyase from Granulicella tundricola (GtHNL), which was successfully heterologously expressed in Escherichia coli. The crystal structure was solved at a crystallographic resolution of 2.5 Å and exhibits a cupin fold. As GtHNL does not show any sequence or structural similarity to any other HNL and does not contain conserved motifs typical of HNLs, cupins represent a new class of HNLs. GtHNL is metal-dependent, as confirmed by inductively coupled plasma/optical emission spectroscopy, and in the crystal structure, manganese is bound to three histidine and one glutamine residue. GtHNL displayed a specific activity of 1.74 U·mg(-1) at pH 6 with (R)-mandelonitrile, and synthesized (R)-mandelonitrile with 90% enantiomeric excess at 80% conversion using 0.5 m benzaldehyde in a biphasic reaction system with methyl tertiary butyl ether.

PubMed: 23981508
DOI: 10.1111/FEBS.12501

Experimental method

X-RAY DIFFRACTION (2.46 Å)