3PT5

Crystal structure of NanS

Summary for 3PT5

• Entry DOI: 10.2210/pdb3pt5/pdb
• Descriptor: NANS (YJHS), A 9-O-acetyl N-acetylneuraminic acid esterase (2 entities in total)
• Functional Keywords: sgnh hydrolase, 9-o-acetyl n-acetylneuraminic acid esterase, structural genomics, montreal-kingston bacterial structural genomics initiative, bsgi, hydrolase
• Biological source: Escherichia coli O157:H7 EDL933
• Total number of polymer chains: 1
• Total formula weight: 38127.18

Authors

Ruane, K.M.,Rangarajan, E.S.,Proteau, A.,Schrag, J.D.,Cygler, M.,Montreal-Kingston Bacterial Structural Genomics Initiative (BSGI) (deposition date: 2010-12-02, release date: 2011-05-18, Last modification date: 2024-02-21)

Primary citation

Rangarajan, E.S.,Ruane, K.M.,Proteau, A.,Schrag, J.D.,Valladares, R.,Gonzalez, C.F.,Gilbert, M.,Yakunin, A.F.,Cygler, M.
Structural and enzymatic characterization of NanS (YjhS), a 9-O-Acetyl N-acetylneuraminic acid esterase from Escherichia coli O157:H7.
Protein Sci., 20:1208-1219, 2011

PubMed Abstract: There is a high prevalence of sialic acid in a number of different organisms, resulting in there being a myriad of different enzymes that can exploit it as a fermentable carbon source. One such enzyme is NanS, a carbohydrate esterase that we show here deacetylates the 9 position of 9-O-sialic acid so that it can be readily transported into the cell for catabolism. Through structural studies, we show that NanS adopts a SGNH hydrolase fold. Although the backbone of the structure is similar to previously characterized family members, sequence comparisons indicate that this family can be further subdivided into two subfamilies with somewhat different fingerprints. NanS is the founding member of group II. Its catalytic center contains Ser19 and His301 but no Asp/Glu is present to form the classical catalytic triad. The contribution of Ser19 and His301 to catalysis was confirmed by mutagenesis. In addition to structural characterization, we have mapped the specificity of NanS using a battery of substrates.

PubMed: 21557376
DOI: 10.1002/pro.649

Experimental method

X-RAY DIFFRACTION (1.6 Å)