Greene, Patricia J.Yu, Pak-LamZhao, JiaSchiffer, Celia A.Santi, Daniel V.2022-08-232022-08-231994-07-012010-02-05Protein Sci. 1994 Jul;3(7):1114-6. <a href="http://dx.doi.org/10.1002/pro.5560030715">Link to article on publisher's site</a>0961-8368 (Print)10.1002/pro.55600307157920258https://hdl.handle.net/20.500.14038/25974The thymidylate synthase (TS) gene from Lactococcus lactis has been highly expressed in Escherichia coli. The TS protein was purified by sequential chromatography on Q-Sepharose and phenyl-Sepharose. Six grams of cell pellet yielded 140 mg of homogeneous TS. TS is a highly conserved enzyme, and several of the conserved amino acid residues that have been implicated in catalytic function are altered in L. lactis TS. By use of a 3-dimensional homology model, we have predicted covariant changes that might compensate for these differences. With the large amounts of L. lactis TS now available, studies can be pursued to understand the structure-function relationships of this enzyme compared to other TSs and to confirm the presumed roles of the compensatory changes predicted in the homology model.en-USAmino Acid SequenceBinding SitesCrystallizationEscherichia coli*Gene ExpressionHydrogen-Ion ConcentrationLactococcus lactisModels, MolecularMolecular Sequence DataMolecular StructureOsmolar ConcentrationRecombinant ProteinsStructure-Activity RelationshipThymidylate SynthaseBiochemistry, Biophysics, and Structural BiologyPharmacology, Toxicology and Environmental HealthJournal Articlehttps://escholarship.umassmed.edu/bmp_pp/1021134075bmp_pp/102