title: Capillary electrophoretic analysis of serine hydroxymethyltransferase in Escherichia coli fermentation broth.
abstract: Serine hydroxymethyltransferase (SHMT) expressed in Escherichia coli was analyzed in fermentation broth through the use of capillary electrophoresis (CE), a method which provided advantages over the traditional techniques of slab gel electrophoresis and chromatography. In addition, via CE the difficult resolution and quantitation of SHMT holoenzyme and apoenzyme were achieved. Using this method, a pyridoxal-5'-phosphate (PLP) cofactor/SHMT dimer molar ratio of 0.65 was estimated to be present in holoenzyme in the absence of excess PLP. This determination correlated well with results obtained by other techniques, including electrospray ionization mass spectrometry (ESI-MS). CE and ESI-MS analyses both provided evidence for significant differences between the folded conformations of SHMT holoenzyme and apoenzyme.
authors.affiliation: Lilly Research Laboratories, A Division of Eli Lilly and Company, Indianapolis, Indiana 46285.
authors.forename: M A
authors.initials: MA
authors.lastname: Strege
authors.forename: D F
authors.initials: DF
authors.lastname: Schmidt
authors.forename: A
authors.initials: A
authors.lastname: Kreuzman
authors.forename: J
authors.initials: J
authors.lastname: Dotzlaf
authors.forename: W K
authors.initials: WK
authors.lastname: Yeh
authors.forename: R E
authors.initials: RE
authors.lastname: Kaiser
authors.forename: A L
authors.initials: AL
authors.lastname: Lagu
mesh_terms: D001051:Apoenzymes / Q000032:analysis / Q000737:chemistry / Q000235:genetics; D002021:Buffers; D004586:Electrophoresis / Q000379:methods*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005285:Fermentation; D012696:Glycine Hydroxymethyltransferase / Q000032:analysis* / Q000737:chemistry / Q000235:genetics; D006863:Hydrogen-Ion Concentration; D013058:Mass Spectrometry / Q000379:methods; D008970:Molecular Weight; D017510:Protein Folding; D011994:Recombinant Proteins / Q000032:analysis / Q000737:chemistry / Q000235:genetics
chemical_list: D001051:Apoenzymes; D002021:Buffers; D011994:Recombinant Proteins; D012696:Glycine Hydroxymethyltransferase