Structural Snapshots of an Engineered Cystathionine-γ-lyase Reveal the Critical Role of Electrostatic Interactions in the Active Site.

ABSTRACT: Enzyme therapeutics that can degrade l-methionine (l-Met) are of great interest as numerous malignancies are exquisitely sensitive to l-Met depletion. To exhaust the pool of methionine in human serum, we previously engineered an l-Met-degrading enzyme based on the human cystathionine-γ-lyase scaffold (hCGL-NLV) to circumvent immunogenicity and stability issues observed in the preclinical application of bacterially derived methionine-γ-lyases. To gain further insights into the structure-activity relationships governing the chemistry of the hCGL-NLV lead molecule, we undertook a biophysical characterization campaign that captured crystal structures (2.2 Å) of hCGL-NLV with distinct reaction intermediates, including internal aldimine, substrate-bound, gem-diamine, and external aldimine forms.

SUBMITTER: Yan W 

PROVIDER: S-EPMC5376214 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature