1GK3

Histidine Ammonia-Lyase (HAL) Mutant D145A from Pseudomonas putida

Summary for 1GK3

• Entry DOI: 10.2210/pdb1gk3/pdb
• Related: 1B8F 1EB4 1GK2 1GKJ 1GKM
• Descriptor: HISTIDINE AMMONIA-LYASE, SULFATE ION, GLYCEROL, ... (4 entities in total)
• Functional Keywords: lyase, ammonia-lyase, histidine degradation
• Biological source: PSEUDOMONAS PUTIDA
• Total number of polymer chains: 1
• Total formula weight: 53799.40

Authors

Baedeker, M.,Schulz, G.E. (deposition date: 2001-08-07, release date: 2002-02-21, Last modification date: 2024-05-08)

Primary citation

Baedeker, M.,Schulz, G.E.
Autocatalytic Peptide Cyclization During Chain Folding of Histidine Ammonia-Lyase.
Structure, 10:61-67, 2002

PubMed Abstract: Histidine ammonia-lyase requires a 4-methylidene-imidazole-5-one group (MIO) that is produced autocatalytically by a cyclization and dehydration step in a 3-residue loop of the polypeptide. The crystal structures of three mutants have been established. Two mutants were inactive and failed to form MIO, but remained unchanged elsewhere. The third mutant showed very low activity and formed MIO, although it differed from an MIO-less mutant only by an additional 329-C(beta) atom. This atom forms one constraint during MIO formation, the other being the strongly connected Asp145. An exploration of the conformational space of the MIO-forming loop showed that the cyclization is probably enforced by a mechanic compression in a late stage of chain folding and is catalyzed by a well-connected internal water molecule. The cyclization of the respective 3-residue loop of green fluorescent protein is likely to occur in a similar reaction.

PubMed: 11796111
DOI: 10.1016/S0969-2126(01)00692-X

Experimental method

X-RAY DIFFRACTION (2.25 Å)