2ZCF

Mutational study on Alpha-Gln90 of Fe-type nitrile hydratase from Rhodococcus sp. N771

Summary for 2ZCF

• Entry DOI: 10.2210/pdb2zcf/pdb
• Related: 1AHJ 2AHJ 2CYZ 2CZ0 2CZ1 2D0Q
• Descriptor: Nitrile hydratase subunit alpha, Nitrile hydratase subunit beta, FE (III) ION, ... (5 entities in total)
• Functional Keywords: cysteine-sulfinic acid, cysteine-sulfenic acid, photo-reactive, nitrile, hydration, photo-activation, iron, lyase, metal-binding, oxidation, structural genomics, nppsfa, national project on protein structural and functional analyses, riken structural genomics/proteomics initiative, rsgi
• Biological source: Rhodococcus erythropolis; More
• Total number of polymer chains: 2
• Total formula weight: 46514.30

Authors

Takarada, H.,Kawano, Y.,Hashimoto, K.,Nakayama, H.,Ueda, S.,Yohda, M.,Kamiya, N.,Dohmae, N.,Maeda, M.,Odaka, M.,RIKEN Structural Genomics/Proteomics Initiative (RSGI) (deposition date: 2007-11-08, release date: 2007-11-20, Last modification date: 2024-10-09)

Primary citation

Takarada, H.,Kawano, Y.,Hashimoto, K.,Nakayama, H.,Ueda, S.,Yohda, M.,Kamiya, N.,Dohmae, N.,Maeda, M.,Odaka, M.
Mutational study on alphaGln90 of Fe-type nitrile hydratase from Rhodococcus sp. N771
Biosci.Biotechnol.Biochem., 70:881-889, 2006

PubMed Abstract: Nitrile hydratase (NHase) from Rhodococcus sp. N771 is a non-heme iron enzyme having post-translationally modified cysteine ligands, alphaCys112-SO2H and alphaCys114-SOH. We replaced alphaGln90, which is conserved in all known NHases and involved in the hydrogen-bond network around the catalytic center, with glutamic acid or asparagine. The kcat of alphaQ90E and alphaQ90N mutants decreased to 24% and 5% that of wild type respectively, but the effect of mutations on Km was not very significant. In both mutants, the alphaCys114-SOH modification appeared to be responsible for the catalysis as in native NHase. We crystallized the nitrosylated alphaQ90N mutant and determined its structure at a resolution of 1.43 A. The structure was basically identical to that of native nitrosylated NHase except for the mutated site and its vicinity. The structural difference between native and alphaQ90N mutant NHases suggested the importance of the hydrogen bond networks between alphaGln90 and the iron center for the catalytic activity.

PubMed: 16636455
DOI: 10.1271/bbb.70.881

Experimental method

X-RAY DIFFRACTION (1.43 Å)