title: Hyperthermophilic aldolases as biocatalyst for C-C bond formation: rhamnulose 1-phosphate aldolase from Thermotoga maritima.
abstract: The TM1072 gene from Thermotoga maritima codifies for a putative form of a rhamnulose-1-phosphate aldolase (Rha-1PA Tm). To investigate this enzyme further, its gene was cloned and expressed in Escherichia coli. The purified enzyme was activated by Co(2+) as a divalent metal ion cofactor, instead of Zn(2+) as its E. coli homologue, and exhibited a maximum of activity at 95 °C. Furthermore, the enzyme displayed a high stability against extreme reaction conditions, retaining 90 % of its activity in the presence of 40 % of acetonitrile and showing a half-life greater than 3 h at 115 °C. The kinetic parameters at room temperature (R/T) were also studied; the K M was calculated to be 3.6 ± 0.33 mM, while k cat/K M was found to be 0.7 × 10(3) s(-1) M(-1). Given these characteristics, Rha-1PA Tm is an attractive enzyme for use as a biocatalyst for industrial applications, offering intriguing possibilities for practical biocatalysis.
authors.affiliation: Departamento de Química Bioorgánica, Instituto de Química Orgánica General, CSIC, Juan de la Cierva 3, 28006, Madrid, Spain.
authors.forename: Isabel
authors.initials: I
authors.lastname: Oroz-Guinea
authors.forename: Israel
authors.initials: I
authors.lastname: Sánchez-Moreno
authors.forename: Montaña
authors.initials: M
authors.lastname: Mena
authors.forename: Eduardo
authors.initials: E
authors.lastname: García-Junceda
mesh_terms: D000446:Aldehyde-Lyases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D000595:Amino Acid Sequence; D002384:Catalysis; D003001:Cloning, Molecular; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics; D006207:Half-Life; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013696:Temperature; D020124:Thermotoga maritima / Q000201:enzymology* / Q000235:genetics
chemical_list: D011994:Recombinant Proteins; D000446:Aldehyde-Lyases; C022526:rhamnulose-1-phosphate adolase