title: Mutation of Gly-444 inactivates the S. pombe malic enzyme.
abstract: A mutant malic enzyme gene, mae2-, was cloned from a strain of Schizosaccharomyces pombe that displayed almost no malic enzyme activity. Sequence analysis revealed only one codon-altering mutation, a guanine to adenine at nucleotide 1331, changing the glycine residue at position 444 to an aspartate residue. Gly-444 is located in Region H, previously identified as one of eight highly conserved regions in malic enzymes. We found that Gly-444 is absolutely conserved in 27 malic enzymes from various prokaryotic and eukaryotic sources, as well as in three bacterial malolactic enzymes investigated. The evolutionary conservation of Gly-444 suggests that this residue is important for enzymatic function.
authors.affiliation: Department of Microbiology, University of Stellenbosch, Matieland, South Africa.
authors.forename: M
authors.initials: M
authors.lastname: Viljoen
authors.forename: M
authors.initials: M
authors.lastname: van der Merwe
authors.forename: R E
authors.initials: RE
authors.lastname: Subden
authors.forename: H J
authors.initials: HJ
authors.lastname: van Vuuren
mesh_terms: D000595:Amino Acid Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004271:DNA, Fungal / Q000032:analysis; D005800:Genes, Fungal; D005998:Glycine / Q000737:chemistry; D008291:Malate Dehydrogenase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008293:Malates / Q000378:metabolism; D008969:Molecular Sequence Data; D017354:Point Mutation; D016133:Polymerase Chain Reaction / Q000379:methods; D015183:Restriction Mapping; D012568:Schizosaccharomyces / Q000201:enzymology* / Q000235:genetics; D017422:Sequence Analysis, DNA; D013329:Structure-Activity Relationship
chemical_list: D004271:DNA, Fungal; D008293:Malates; D008291:Malate Dehydrogenase; D005998:Glycine