標題: Identification of amino acid residues important for the phosphomannose isomerase activity of Ps1B in Pseudomonas aeruginosa PAO1
作者: Lee, Hui-Ju
Chang, Hwan-You
Venkatesan, Nandinin
Peng, Hwei-Ling
生物科技學院
College of Biological Science and Technology
關鍵字: GDP-mannose pyrophosphorylase;Pseudomonas aeruginosa;Phosphomannose isomerase;pslB;Site-directed mutagenesis
公開日期: 15-Oct-2008
摘要: Phosphomannose isomerase (PMI) plays a pivotal role in biosynthesis of GDP-mannose, an important precursor of many polysaccharides. We demonstrate in this study that Pseudomonas aeruginosa pslB encodes a protein with GDP-mannose pyrophosphorylase/PMI dual activities. The PMI activity is Co2+-dependent and could be inhibited by GDP-mannose in a competitive manner. Furthermore, the activity could be inactivated by 2,3-butanedione suggesting the presence of a catalytic Arg residue. Site-specific mutations at R373, R472, R479, E410, H411, N433 and E458 increase the KM approximately 8-20-fold. The PMI activity of PslB was completely diminished with a R408K or R408A, reflecting the importance of this residue in catalysis. Overall, these results provide a basis for understanding the catalytic mechanism of PMI.
URI: http://dx.doi.org/10.1016/j.febslet.2008.09.013
http://hdl.handle.net/11536/8245
ISSN: 0014-5793
DOI: 10.1016/j.febslet.2008.09.013
期刊: FEBS LETTERS
Volume: 582
Issue: 23-24
起始頁: 3479
結束頁: 3483
Appears in Collections:Articles


Files in This Item:

  1. 000260806700038.pdf