title: Substrate spectrum of L-rhamnulose kinase related to models derived from two ternary complex structures.
abstract: The enzyme L-rhamnulose kinase from Escherichia coli participates in the degradation pathway of L-rhamnose, a common natural deoxy-hexose. The structure of the enzyme in a ternary complex with its substrates ADP and L-rhamnulose has been determined at 1.55A resolution and refined to R(cryst)/R(free) values of 0.179/0.209. The result was compared with the lower resolution structure of a corresponding complex containing L-fructose instead of L-rhamnulose. In light of the two established sugar positions and conformations, a number of rare sugars have been modeled into the active center of L-rhamnulose kinase and the model structures have been compared with the known enzymatic phosphorylation rates. Rare sugars are of rising interest for the synthesis of bioactive compounds.
authors.affiliation: Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität, Albertstrasse 21, 79104 Freiburg im Breisgau, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Grueninger
authors.forename: Georg E
authors.initials: GE
authors.lastname: Schulz
mesh_terms: D000244:Adenosine Diphosphate / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000201:enzymology*; D006601:Hexoses / Q000737:chemistry / Q000378:metabolism; D007536:Isomerism; D008958:Models, Molecular; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000737:chemistry* / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012210:Rhamnose / Q000378:metabolism; D013329:Structure-Activity Relationship; D013379:Substrate Specificity
chemical_list: D006601:Hexoses; D000244:Adenosine Diphosphate; D017853:Phosphotransferases (Alcohol Group Acceptor); C062877:rhamnulokinase; D012210:Rhamnose