Publication Date:
2015-07-04
Description:
Lactic acid racemization is involved in lactate metabolism and cell wall assembly of many microorganisms. Lactate racemase (Lar) requires nickel, but the nickel-binding site and the role of three accessory proteins required for its activation remain enigmatic. We combined mass spectrometry and x-ray crystallography to show that Lar from Lactobacillus plantarum possesses an organometallic nickel-containing prosthetic group. A nicotinic acid mononucleotide derivative is tethered to Lys(184) and forms a tridentate pincer complex that coordinates nickel through one metal-carbon and two metal-sulfur bonds, with His(200) as another ligand. Although similar complexes have been previously synthesized, there was no prior evidence for the existence of pincer cofactors in enzymes. The wide distribution of the accessory proteins without Lar suggests that it may play a role in other enzymes.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Desguin, Benoit -- Zhang, Tuo -- Soumillion, Patrice -- Hols, Pascal -- Hu, Jian -- Hausinger, Robert P -- New York, N.Y. -- Science. 2015 Jul 3;349(6243):66-9. doi: 10.1126/science.aab2272.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA. ; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA. ; Institute of Life Sciences, Universite Catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium. ; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA. Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA. hujian1@msu.edu hausinge@msu.edu. ; Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA. Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA. hujian1@msu.edu hausinge@msu.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26138974" target="_blank"〉PubMed〈/a〉
Keywords:
Bacterial Proteins/*chemistry/genetics
;
Binding Sites
;
Carbon/chemistry
;
Catalysis
;
Crystallography, X-Ray
;
Histidine/chemistry
;
Holoenzymes/chemistry
;
Lactic Acid/*biosynthesis/chemistry
;
Lactobacillus plantarum/*enzymology/genetics
;
Ligands
;
Lysine/chemistry
;
Metalloproteins/*chemistry/genetics
;
Niacin/*chemistry
;
Nickel/*chemistry
;
Nicotinamide Mononucleotide/analogs & derivatives/chemistry
;
Protein Processing, Post-Translational
;
Protein Structure, Secondary
;
Racemases and Epimerases/*chemistry/genetics
;
Spectrometry, Mass, Electrospray Ionization
;
Sulfur
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
