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bioRxiv · 10.1101/2020.11.11.379065

Biophysical characterization of two commercially available preparations of the drug containing Escherichia coli L-Asparaginase 2

Araujo, T. S.·Scapin, S. M.·Andrade, W.·Fasciotti, M.·de Magalhaes, M. T.·Almeida, M. S.·Lima, L. M. T. d. R.
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Abstract

The hydrolysis of asparagine and glutamine by L-asparaginase has been used to treat acute lymphoblastic leukemia for over four decades. Each L-asparaginase monomer has a long loop that closes over the active site upon substrate binding, acting as a lid. Here we present a comparative study two commercially available preparations of the drug containing Escherichia coli L-Asparaginase 2, performed by a comprehensive array of biophysical and biochemical approaches. We report the oligomeric landscape and conformational and dynamic plasticity of E. coli type 2 L-asparaginase (EcA2) present in two different formulations, and its relationship with L-aspartic acid, which is present in Aginasa, but not in Leuginase. EcA2 shows a composition of monomers and oligomers up to tetramers, which is mostly not altered in the presence of L-Asp. The N-terminal loop of Leuginase, which is part of the active site is flexibly disordered, but gets ordered as in Aginasa in the presence os L-Asp, while L-Glu only does so to a limited extent. Ion-mobility spectrometry-mass spectrometry reveals two conformers for the monomeric EcA2, one of which can selectively bind to L-Asp and L-Glu. Aginasa has higher resistance to in vitro proteolysis than Leuginase, and this is directly related to the presence of L-Asp.

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Araujo, T. S., Scapin, S. M., Andrade, W., Fasciotti, M., de Magalhaes, M. T., Almeida, M. S., Lima, L. M. T. d. R.. 2020-11-12. Biophysical characterization of two commercially available preparations of the drug containing Escherichia coli L-Asparaginase 2. https://doi.org/10.1101/2020.11.11.379065

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