9QCW

Crystal structure of Rhizobium etli L-asparaginase ReAV K51A mutant

Summary for 9QCW

• Entry DOI: 10.2210/pdb9qcw/pdb
• Related: 7OS3 7OS5 7OS6 7OU1 7OZ6 8CLY 8CLZ 8COL 8ORI 8OSW 8RUA 8RUD 8RUE 8RUF 8RUG 9G66 9G67 9G68
• Descriptor: L-asparaginase II, 1,2-ETHANEDIOL, SULFATE ION, ... (7 entities in total)
• Functional Keywords: rhizobium etli; amidohydrolases; l-asparaginases; site-directed mutagenesis, hydrolase
• Biological source: Rhizobium etli
• Total number of polymer chains: 2
• Total formula weight: 80681.97

Authors

Pokrywka, K.,Grzechowiak, M.,Loch, J.I.,Ruszkowski, M.,Gilski, M.,Jaskolski, M. (deposition date: 2025-03-05, release date: 2025-07-16, Last modification date: 2025-08-06)

Primary citation

Pokrywka, K.,Grzechowiak, M.,Sliwiak, J.,Worsztynowicz, P.,Loch, J.I.,Ruszkowski, M.,Gilski, M.,Jaskolski, M.
Probing the Active Site of Class 3 L-Asparaginase by Mutagenesis: Mutations of the Ser-Lys Tandems of ReAV.
Biomolecules, 15:-, 2025

PubMed Abstract: The ReAV enzyme from , a representative of Class 3 L-asparaginases, is sequentially and structurally different from other known L-asparaginases. This distinctiveness makes ReAV a candidate for novel antileukemic therapies. ReAV is a homodimeric protein, with each subunit containing a highly specific zinc-binding site created by two cysteines, a lysine, and a water molecule. Two Ser-Lys tandems (Ser48-Lys51, Ser80-Lys263) are located in the close proximity of the metal binding site, with Ser48 hypothesized to be the catalytic nucleophile. To further investigate the catalytic process of ReAV, site-directed mutagenesis was employed to introduce alanine substitutions at residues from the Ser-Lys tandems and at Arg47, located near the Ser48-Lys51 tandem. These mutational studies, along with enzymatic assays and X-ray structure determinations, demonstrated that substitution of each of these highly conserved residues abolished the catalytic activity, confirming their essential role in enzyme mechanism.

PubMed: 40723816
DOI: 10.3390/biom15070944

Experimental method

X-RAY DIFFRACTION (1.95 Å)