title: Molecular characterization of a novel N-acetylneuraminate lyase from Lactobacillus plantarum WCFS1.
abstract: N-Acetylneuraminate lyases (NALs) or sialic acid aldolases catalyze the reversible aldol cleavage of N-acetylneuraminic acid (Neu5Ac) to form pyruvate and N-acetyl-d-mannosamine (ManNAc). In nature, N-acetylneuraminate lyase occurs mainly in pathogens. However, this paper describes how an N-acetylneuraminate lyase was cloned from the human gut commensal Lactobacillus plantarum WCFS1 (LpNAL), overexpressed, purified, and characterized for the first time. This novel enzyme, which reaches a high expression level (215 mg liter(-1) culture), shows similar catalytic efficiency to the best NALs previously described. This homotetrameric enzyme (132 kDa) also shows high stability and activity at alkaline pH (pH > 9) and good temperature stability (60 to 70°C), this last feature being further improved by the presence of stabilizing additives. These characteristics make LpNAL a promising biocatalyst. When its sequence was compared with that of other, related (real and putative) NALs described in the databases, it was seen that NAL enzymes could be divided into four structural groups and three subgroups. The relation of these subgroups with human and other mammalian NALs is also discussed.
authors.affiliation: Department of Biochemistry and Molecular Biology-A, Faculty of Biology, University of Murcia, Campus Espinardo, E30011 Murcia, Spain.
authors.forename: Guiomar
authors.initials: G
authors.lastname: Sánchez-Carrón
authors.forename: María Inmaculada
authors.initials: MI
authors.lastname: García-García
authors.forename: Ana Belén
authors.initials: AB
authors.lastname: López-Rodríguez
authors.forename: Sofía
authors.initials: S
authors.lastname: Jiménez-García
authors.forename: Agustín
authors.initials: A
authors.lastname: Sola-Carvajal
authors.forename: Francisco
authors.initials: F
authors.lastname: García-Carmona
authors.forename: Alvaro
authors.initials: A
authors.lastname: Sánchez-Ferrer
mesh_terms: D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D016000:Cluster Analysis; D004795:Enzyme Stability; D015870:Gene Expression; D006595:Hexosamines / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D048191:Lactiplantibacillus plantarum / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009438:Neuraminic Acids / Q000378:metabolism; D007652:Oxo-Acid-Lyases / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D055503:Protein Multimerization; D019289:Pyruvic Acid / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013696:Temperature
chemical_list: D006595:Hexosamines; D009438:Neuraminic Acids; D011994:Recombinant Proteins; D019289:Pyruvic Acid; D007652:Oxo-Acid-Lyases; C018728:N-acetylneuraminate lyase; C002022:N-acetylmannosamine