title: Three-dimensional structure of Serratia marcescens nuclease at 1.7 A resolution and mechanism of its action.
abstract: The three-dimensional crystal structure of Serratia marcescens (Sm) nuclease has been refined at 1.7 A resolution to the R-factor of 17.3% and R-free of 22.2%. The final model consists of 3678 non-hydrogen atoms and 443 water molecules. The analysis of the secondary and the tertiary structures of the Sm nuclease suggests a topology which reveals essential inner symmetry in all the three layers forming the monomer. We propose the plausible mechanism of its action based on a concerted participation of the catalytically important amino acid residues of the enzyme active site.
authors.affiliation: Institute of Mathematical Problems in Biology, Russian Academy of Sciences, Pushino, Moscow region.
authors.forename: V Y
authors.initials: VY
authors.lastname: Lunin
authors.forename: V M
authors.initials: VM
authors.lastname: Levdikov
authors.forename: S V
authors.initials: SV
authors.lastname: Shlyapnikov
authors.forename: E V
authors.initials: EV
authors.lastname: Blagova
authors.forename: V V
authors.initials: VV
authors.lastname: Lunin
authors.forename: K S
authors.initials: KS
authors.lastname: Wilson
authors.forename: A M
authors.initials: AM
authors.lastname: Mikhailov
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D003460:Crystallization; D018360:Crystallography, X-Ray; D004706:Endodeoxyribonucleases / Q000737:chemistry*; D004722:Endoribonucleases / Q000737:chemistry*; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
chemical_list: D004706:Endodeoxyribonucleases; D004722:Endoribonucleases; C021835:Serratia marcescens nuclease