%0 Journal Article %J Acta Crystallogr F Struct Biol Commun %D 2018 %T Crystal structures and kinetics of N-acetylneuraminate lyase from Fusobacterium nucleatum. %A Kumar, Jay Prakash %A Rao, Harshvardhan %A Nayak, Vinod %A Ramaswamy, S %K Bacterial Proteins %K Crystallography, X-Ray %K Fusobacterium nucleatum %K Hydrogen Bonding %K Models, Molecular %K N-Acetylneuraminic Acid %K Oxo-Acid-Lyases %K Protein Conformation %K Protein Folding %K Pyruvic Acid %K Schiff Bases %K Sequence Alignment %K Tyrosine %X

N-Acetyl-D-neuraminic acid lyase (NanA) catalyzes the breakdown of sialic acid (Neu5Ac) to N-acetyl-D-mannosamine (ManNAc) and pyruvate. NanA plays a key role in Neu5Ac catabolism in many pathogenic and bacterial commensals where sialic acid is available as a carbon and nitrogen source. Several pathogens or commensals decorate their surfaces with sialic acids as a strategy to escape host innate immunity. Catabolism of sialic acid is key to a range of host-pathogen interactions. In this study, atomic resolution structures of NanA from Fusobacterium nucleatum (FnNanA) in ligand-free and ligand-bound forms are reported at 2.32 and 1.76 Å resolution, respectively. F. nucleatum is a Gram-negative pathogen that causes gingival and periodontal diseases in human hosts. Like other bacterial N-acetylneuraminate lyases, FnNanA also shares the triosephosphate isomerase (TIM)-barrel fold. As observed in other homologous enzymes, FnNanA forms a tetramer. In order to characterize the structure-function relationship, the steady-state kinetic parameters of the enzyme are also reported.

%B Acta Crystallogr F Struct Biol Commun %V 74 %P 725-732 %8 2018 Nov 01 %G eng %N Pt 11 %R 10.1107/S2053230X18012992