2H0R

Structure of the Yeast Nicotinamidase Pnc1p

Summary for 2H0R

• Entry DOI: 10.2210/pdb2h0r/pdb
• Descriptor: Nicotinamidase, ZINC ION (2 entities in total)
• Functional Keywords: nicotinamidase, nad+ salvage pathway, hydrolase
• Biological source: Saccharomyces cerevisiae (baker's yeast)
• Cellular location: Cytoplasm: P53184
• Total number of polymer chains: 7
• Total formula weight: 175670.19

Authors

Taylor, A.B.,Hu, G.,Hart, P.J.,McAlister-Henn, L. (deposition date: 2006-05-15, release date: 2007-03-27, Last modification date: 2024-02-14)

Primary citation

Hu, G.,Taylor, A.B.,McAlister-Henn, L.,Hart, P.J.
Crystal structure of the yeast nicotinamidase Pnc1p.
Arch.Biochem.Biophys., 461:66-75, 2007

PubMed Abstract: The yeast nicotinamidase Pnc1p acts in transcriptional silencing by reducing levels of nicotinamide, an inhibitor of the histone deacetylase Sir2p. The Pnc1p structure was determined at 2.9A resolution using MAD and MIRAS phasing methods after inadvertent crystallization during the pursuit of the structure of histidine-tagged yeast isocitrate dehydrogenase (IDH). Pnc1p displays a cluster of surface histidine residues likely responsible for its co-fractionation with IDH from Ni(2+)-coupled chromatography resins. Researchers expressing histidine-tagged proteins in yeast should be aware of the propensity of Pnc1p to crystallize, even when overwhelmed in concentration by the protein of interest. The protein assembles into extended helical arrays interwoven to form an unusually robust, yet porous superstructure. Comparison of the Pnc1p structure with those of three homologous bacterial proteins reveals a common core fold punctuated by amino acid insertions unique to each protein. These insertions mediate the self-interactions that define the distinct higher order oligomeric states attained by these molecules. Pnc1p also acts on pyrazinamide, a substrate analog converted by the nicotinamidase from Mycobacterium tuberculosis into a product toxic to that organism. However, we find no evidence for detrimental effects of the drug on yeast cell growth.

PubMed: 17382284
DOI: 10.1016/j.abb.2007.01.037

Experimental method

X-RAY DIFFRACTION (2.9 Å)