Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:5.4.2.8 (phosphomannomutase)
 238 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this article is to analyze conformational changes by comparing 10 different structures of Pseudomonas aeruginosa phosphomannomutase/phosphoglucomutase (PMM/PGM), a four-domain enzyme in which both substrate binding and catalysis require substantial movement of the C-terminal domain. We focus on changes in interdomain and active site crevices using a method called computational solvent mapping rather than superimposing the structures. The method places molecular probes (i.e., small organic molecules containing various functional groups) around the protein to find hot spots. One of the most important hot spots is in the active site, consistent with the ability of the enzyme to bind both glucose and mannose phosphosugar substrates. The protein has eight additional hot spots at domain-domain interfaces and hinge regions. The locations and nature of six of these hot spots vary between the open, half-open, and closed conformers of the enzyme, in good agreement with the ligand-induced conformational changes. In the closed structures the number of probe clusters at the hinge region significantly depends on the position of the phosphorylated oxygen in the substrate (e.g., glucose 1-phosphate versus glucose 6-phosphate), but the protein remains almost unchanged in terms of the overall RMSD, indicating that computational solvent mapping is a more sensitive approach to detect changes in binding sites and interdomain crevices. Focusing on multidomain proteins we show that the subresolution conformational differences revealed by the mapping are in fact significant, and present a general statistical method of analysis to determine the significance of rigid body domain movements in X-ray structures.
Protein Sci 2010 Sep
PMID:Domain motion and interdomain hot spots in a multidomain enzyme. 2058 4

Acerola fruits contain abundant ascorbic acid (AsA). The gene expression levels of three upstream enzymes in the primary AsA biosynthesis pathway were correlated with AsA contents in the fruits of two acerola cultivars. Multiple overexpression of the enzymes increased AsA contents, suggesting their high expression is important for high AsA accumulation in acerola fruits and the breeding of AsA-rich plants. Abbreviations: AsA: ascorbic acid; PMI: phosphomannose isomerase; PMM: phosphomannomutase; GMP: GDP-d-mannose pyrophosphorylase; GME: GDP-d-mannose 3',5'-epimerase; GGP: GDP-l-galactose phosphorylase; GPP: l-galactose-1-phosphate phosphatase; GDH: l-galactose dehydrogenase; GLDH: l-galactono-1,4-lactone dehydrogenase.
Biosci Biotechnol Biochem 2019 Sep
PMID:High levels of expression of multiple enzymes in the Smirnoff-Wheeler pathway are important for high accumulation of ascorbic acid in acerola fruits. 3102 55

GDP-mannose is an important precursor for the synthesis of Codonopsis pilosula polysaccharides and involved in the synthesis of sugar chains. Phosphomannomutase(PMM)catalyzes the conversion of mannose-6-phosphate(Man-6-P)to mannose-1-phosphate(Man-1-P)to synthesize GDP-mannose. In this study, specific primers were designed based on the PMM gene sequence information in transcriptome data, and the full length of the C. pilosula PMM gene was cloned and named CpPMM. The correlation between the CpPMM gene expression and C. pilosula polysaccharide synthesis was analyzed by a series of bioinformatics analysis, prokaryotic expression and qRT-PCR. The results show that the CpPMM gene contains a 741 bp open reading frame(ORF), encoding 246 amino acids, which is highly similar to the PMM of other species and highly homologous to the Helianthus annuus from the Asteraceae family. It was predicted to be a hydrophilic non-transmembrane protein without signal peptide, which was predicted to be located in the cytoplasm with multiple phosphorylation sites. Combined with predictive analysis of conserved domains, this protein belongs to the HAD(haloacid dehalogenase)superfamily; prokaryotic expression studies show that the size of the CpPMM fusion protein is about 29 kDa, which is consistent with the relative molecular mass predicted. The target protein is an inclusion body and is partially soluble. The qRT-PCR results showed that the CpPMM gene exerted spatiotemporal expression patterns, and the expression level in fruiting period was significantly higher than that in the other three periods such as the flowering period. Along with the growth period of C. pilosula, the polysaccharide content of C. pilosula showed a gradual increase trend, reaching the highest during the harvest time. And there are significant differences in the polysaccharide content of C. pilosula in each period. In this study, the CpPMM gene was cloned from the root of C. pilosula, at the same time, the prokaryotic expression system was constructed. In addition, its gene expression level is highly correlated with the polysaccharide content of C. pilosula. It lays the foundation for further studying the function of CpPMM gene and the analysis of biosynthetic pathways of polysaccharides in medicinal plants.
Zhongguo Zhong Yao Za Zhi 2020 Sep
PMID:[Cloning and expression analysis of CpPMM gene in Codonopsis pilosula]. 3316 66


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