4AO6
Native structure of a novel cold-adapted esterase from an Arctic intertidal metagenomic library
Summary for 4AO6
| Entry DOI | 10.2210/pdb4ao6/pdb |
| Related | 4AO7 4AO8 |
| Descriptor | ESTERASE (2 entities in total) |
| Functional Keywords | hydrolase, thermo label |
| Biological source | UNIDENTIFIED |
| Total number of polymer chains | 1 |
| Total formula weight | 28294.19 |
| Authors | Fu, J.,Leiros, H.-K.S.,Pascale, D.d.,Johnson, K.A.,Blencke, H.M.,Landfald, B. (deposition date: 2012-03-23, release date: 2012-08-08, Last modification date: 2024-05-08) |
| Primary citation | Fu, J.,Leiros, H.-K.S.,De Pascale, D.,Johnson, K.A.,Blencke, H.M.,Landfald, B. Functional and Structural Studies of a Novel Cold-Adapted Esterase from an Arctic Intertidal Metagenomic Library. Appl.Microbiol.Biotechnol., 97:3965-, 2013 Cited by PubMed Abstract: A novel cold-adapted lipolytic enzyme gene, est97, was identified from a high Arctic intertidal zone sediment metagenomic library. The deduced amino acid sequence of Est97 showed low similarity with other lipolytic enzymes, the maximum being 30 % identity with a putative lipase from Vibrio caribbenthicus. Common features of lipolytic enzymes, such as the GXSXG sequence motif, were detected. The gene product was over-expressed in Escherichia coli and purified. The recombinant Est97 (rEst97) hydrolysed various ρ-nitrophenyl esters with the best substrate being ρ-nitrophenyl hexanoate (K m and k cat of 39 μM and 25.8 s(-1), respectively). This esterase activity of rEst97 was optimal at 35 °C and pH 7.5 and the enzyme was unstable at temperatures above 25 °C. The apparent melting temperature, as determined by differential scanning calorimetry was 39 °C, substantiating Est97 as a cold-adapted esterase. The crystal structure of rEst97 was determined by the single wavelength anomalous dispersion method to 1.6 Å resolution. The protein was found to have a typical α/β-hydrolase fold with Ser144-His226-Asp197 as the catalytic triad. A suggested, relatively short lid domain of rEst97 is composed of residues 80-114, which form an α-helix and a disordered loop. The cold adaptation features seem primarily related to a high number of methionine and glycine residues and flexible loops in the high-resolution structures. PubMed: 22832985DOI: 10.1007/S00253-012-4276-9 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.6 Å) |
Structure validation
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