Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Starch biogenesis in corn endosperm from Flint, Sugary, Waxy, as a function of the grain filling/period was studied. We have differentially identified the initiation from the elongation process. After incubating under unprimed conditions, two glucose radiolabelled protein bands of 39,5 and 36 kDa were obtained. UDP(14C)Glc was the preferred glucosyl donor but also ADP(14C)Glc was. It was additionally found that more than one glucose was transferred to the protein or to the alpha 1,4-glucan linked to protein from UDPGlc. These results were supported by the fact that the glucosylated protein from UDPGlc liberates maltooligosaccharides after alpha- or beta-amylase treatment. The elongation activity in the first steps related to the glucan linked to protein is different from starch synthase. Therefore, we are proposing a model for starch biogenesis where two new transglucosylating enzyme activities are necessary to prepare the primer for starch synthase.
Cell Mol Biol (Noisy-le-grand) 1994 Nov
PMID:Further studies on the "de novo" process of alpha 1,4-alpha 1,6 glucopolysaccharides--corn starch biogenesis. 784 50

Rhizobium meliloti associates symbiotically with alfalfa by forming root nodules in which the bacteria reduce atmospheric N2 into products useful to both organisms. Nod factors are signal molecules, lipooligosaccharides, produced by the bacteria that trigger nodule formation in the plant host. Nod Rm-1 consists of a beta-1,4-N-acetyl glucosamine tetrasaccharide from which the N-acetyl group at the non reducing end is replaced by a fatty acid and the N-acetyl glucosamine at the reducing end is sulfated at position 6. By in vitro incubation of electroporated cells in the presence of [35S]PAPS or UDP-[14C]GlcNAc a labelled compound has been obtained with the properties of the in vivo produced Nod Rm-1 factor, as judged by HPLC, TLC and HPTLC techniques. The [14C]GlcNAc labelled compound has also hair root deformation activity on alfalfa plantlets indicating that a functional Nod Rm-1 factor has been synthesized in vitro.
Cell Mol Biol (Noisy-le-grand) 1994 Nov
PMID:The in vitro biosynthesis of functional nodulation factors (Nod Rm) produced by Rhizobium meliloti 1021. 784 52

Cloning and nucleotide sequencing indicated that transposon Tn1546 from Enterococcus faecium BM4147 encodes a 23,365 Da protein, VanX, required for glycopeptide resistance. The vanX gene was located downstream from genes encoding the VanA ligase and the VanH dehydrogenase which synthesize the depsipeptide D-alanyl-D-lactate (D-Ala-D-Lac). In the presence of ramoplanin, an Enterococcus faecalis JH2-2 derivative producing VanH, VanA and VanX accumulated mainly UDP-MurNAc-L-Ala-gamma-D-Glu-L-Lys-D-Ala-D-Lac (pentadepsipeptide) and small amounts of UDP-MurNAc-L-Ala-gamma-D-Glu-L-Lys-D-Ala-D-Ala (pentapeptide) in the ratio 49:1. Insertional inactivation of vanX led to increased synthesis of pentapeptide with a resulting change in the ratio of pentadepsipeptide: pentapeptide to less than 1:1. Expression of vanX in E. faecalis and Escherichia coli resulted in production of a D,D-dipeptidase that hydrolysed D-Ala-D-Ala. Pentadepsipeptide, pentapeptide and D-Ala-D-Lac were not substrates for the enzyme. These results establish that VanX is required for production of a D,D-dipeptidase that hydrolyses D-Ala-D-Ala, thereby preventing pentapeptide synthesis and subsequent binding of glycopeptides to D-Ala-D-Ala-containing peptidoglycan precursors at the cell surface.
Mol Microbiol 1994 Sep
PMID:Glycopeptide resistance mediated by enterococcal transposon Tn1546 requires production of VanX for hydrolysis of D-alanyl-D-alanine. 785 21

Indirect evidence has suggested that multiple subunits of microsomal UDP-glucuronosyltransferases (UGTs) are involved in diglucuronide formation of diphenols of polycyclic aromatic hydrocarbons (Bock et al., Mol Pharmacol 42: 613-618, 1992). To substantiate this suggestion functional target sizes of UGTs catalysing these reactions were determined in microsomes in situ by radiation inactivation analysis. Target sizes of UGTs catalysing the glucuronidation of 1-naphthol and 6-hydroxychrysene were found to be 91 +/- 29 and 120 +/- 27 kDa, respectively. However, target sizes for mono- and diglucuronide formation of 3,6-dihydroxybenzo(a)pyrene were 118 +/- 33 and 218 +/- 24 kDa, respectively. Similarly, using 3,6-dihydroxychrysene as substrate target sizes of 109 +/- 21 and 101 +/- 23 kDa were found for 6-O-monoglucuronide and 3-O-monoglucuronide formation and a target size of 192 +/- 34 kDa observed for diglucuronide formation. Based on subunit molecular masses of 50-60 kDa for UGTs, these results suggest that UGTs involved in monoglucuronide formation of phenols may function as dimers. In contrast, UGTs involved in diglucuronide formation of diphenols of polycyclic aromatic hydrocarbons may function as tetramers in microsomes in situ.
 ...
PMID:Radiation inactivation analysis of microsomal UDP-glucuronosyltransferases catalysing mono- and diglucuronide formation of 3,6-dihydroxybenzo(a)pyrene and 3,6-dihydroxychrysene. 798 Jun 19

The purpose of this study was to examine the effects of 13-cis-retinoic acid (13-cis-RA) on the growth regulation of DU-145 human prostatic cancer cells. The results of these experiments demonstrate that cell growth and metastatic potential of DU-145 cells were significantly inhibited by 13-cis-RA (10 microM). In order to elucidate the possible molecular mechanisms of 13-cis-RA action on prostate cancer cells, we examined the expression of nuclear receptor genes (hRXR alpha) and found that 13-cis-RA treated cells showed higher mRNA expression for hRXR alpha nuclear receptors compared to untreated cells. To elucidate further the possible biochemical mechanisms associated with these alterations, we analyzed the phosphorous metabolites by MR spectroscopy and found that the major metabolites were PME, (PC, PE) and DPDE (UDP-GalNAc, UDP-GLcNAc). The DU-145 cells and xenografts, which were both treated with 13-cis-RA, showed a two-fold decrease in DPDE's, compared to their controls. The higher resolution spectra of perfused cells revealed that phosphocholine levels were twice as high in 13-cis-RA-treated DU-145 cells as compared to untreated cells. These investigations demonstrate for the first time that 13-cis-RA inhibits the growth of human prostatic cancer cells, and this inhibition is associated with an increase in hRXR alpha nuclear receptor gene expression and alterations in phosphorous metabolites detected by 31P MR spectroscopy.
Biochem Mol Biol Int 1994 Jan
PMID:13-cis-retinoic acid-mediated growth inhibition of DU-145 human prostate cancer cells. 801 74

The activities of the conjugative enzymes, glutathione S-transferase and UDP-glucuronyl-transferase, have been measured in vitro in the livers of camels, guinea-pigs and rats. Some sex differences were observed in the levels of these conjugative enzymes. In rats and guinea-pigs, females had higher UDP-glucuronyltransferase activity than males. In camels, females had higher glutathione S-transferase activity than males. In these species, the cytochrome P-450 isozymes observed between the 50,000 and 60,000 mol. wt regions have been separated and characterized by SDS-polyacrylamide gel electrophoresis. Camels showed lower levels of all types of cytochrome P-450 isozymes, while guinea-pigs showed higher levels of most of these isozymes. In general, camels seemed to have the lowest drug-metabolizing enzyme activity when compared to rats and guinea-pigs.
Comp Biochem Physiol Biochem Mol Biol 1994 Jul
PMID:Comparison of cytochrome P-450 content and conjugative enzymes in livers of camels (Camelus dromedarius), guinea-pigs (Cavia porcellus) and rats (Rattus norvegicus). 808 58

A proposed weak point in cancer cells is their need to synthesize novel or rare glucosphingolipids. It is further proposed that cancer patients be treated with a drug that slows the synthesis of glucosylceramide, the precursor of a large family of glucosphingolipids. Experimental data are furnished for chemotherapeutic and biochemical effects of PDMP, an analog of glucosylceramide and its precursor, ceramide. Promising results were obtained in the treatment of mice carrying Ehrlich ascites carcinoma cells and rats carrying C6 glioma cells. PDMP was found to be oxidized by cytochrome P-450, but this process could be blocked in vivo with piperonyl butoxide or cimetidine. A high level of blood glucose was found to elevate the size of rat kidneys and their content of UDP-glucose and its product, glucosylceramide. The excessive growth could be blocked by PDMP, which competes with UDP-glc for binding to glucosylceramide synthase. It is suggested that cancer patients be maintained at a low glucose level in order to slow the synthesis of glucosylceramide by tumor cells. Metabolic changes produced by PDMP in cultured cells, besides a rapid deletion of glucosphingolipids, were accumulation of the precursors (ceramide and sphingosine), loss of protein kinase C, and accumulation of diacylglycerol. It is suggested that many of the cellular changes produced by PDMP, such as loss of cell binding, are owing to existence of glucosylceramide-based "islands" floating in the outer cell surface; the islands may contain growth factor receptors and adhesion factors. An inhibitor that blocks sphingolipid synthesis, such as cycloserine, may prove to be a useful adjuvant for therapy with PDMP.
Mol Chem Neuropathol
PMID:Rationales for cancer chemotherapy with PDMP, a specific inhibitor of glucosylceramide synthase. 808 32

ADP is known to be easily determined spectrophotometrically after it is utilized to produce the corresponding amount of NAD by combined reactions of pyruvate kinase and lactate dehydrogenase. We studied whether CDP and UDP can be also determined in a similar manner if they were incubated for a longer period with an increased amount of pyruvate kinase. It was shown that CDP and UDP could be utilized to produce the corresponding amount of NADH oxidized after an incubation of at least 25 min and that 0 to 300 nmols of these nucleotides were able to be determined spectrophotometrically.
Biochem Mol Biol Int 1993 Nov
PMID:Determination of pyrimidine nucleoside diphosphates by use of combined reactions of pyruvate kinase and lactate dehydrogenase. 811 21

A cDNA library produced from mRNA isolated from the pericarp of wild-type tomato fruit (Lycopersicon esculentum Mill. cv Ailsa Craig) at the first visible sign of fruit ripening was differentially screened to identify clones whose homologous mRNAs were present at reduced levels in fruit of the tomato ripening mutant, ripening inhibitor,rin. Five clones were isolated (pERT 1, 10, 13, 14, 15). Accumulation of mRNA homologous to each of these clones increased during the ripening of wild-type fruit and showed reduced accumulation in ripening rin fruit. The levels of three of them (homologous to ERT 1, 13 and 14) were increased by ethylene treatment of the mutant fruit. A further clone, ERT 16 was identified for a mRNA present at a high level in both normal and mutant fruit at early stages of ripening. Database searches revealed no significant homology to the DNA sequence of ERT 14 and 15; however, DNA and derived amino acid sequence of ERT 1 both contain regions of homology with several reported UDP-glucosyl and glucuronosyl transferases (UDPGT) and with a conserved UDPGT motif. A derived amino acid sequence from the ERT 10 cDNA contains a perfect match to a consensus sequence present in a number of dehydrogenases. The ERT 13 DNA sequence has homology with an mRNA present during potato tuberisation. The presence of these mRNAs in tomato fruit is unreported and their role in ripening is unknown. The ERT 16 DNA sequence has homology with a ripening/stress-related cDNA isolated from tomato fruit pericarp.
Plant Mol Biol 1993 Oct
PMID:cDNA cloning and characterisation of novel ripening-related mRNAs with altered patterns of accumulation in the ripening inhibitor (rin) tomato ripening mutant. 821 49

A new HPLC assay was developed to measure UDP-glucose dehydrogenase (UDP-GDH) activity in crude homogenates of 3T3 fibroblasts. UDP-GDH activity is directly related to the proliferative activity of the cell culture: enzyme activity is highest in log phase cells and decreases as the culture approaches quiescence. Serum stimulation of quiescent 3T3 fibroblasts results in an increase in UDP-GDH activity that has two components that are differentially affected by inhibitors of protein synthesis. Following serum stimulation, changes in cellular UDP-glucuronic acid concentrations mirror changes in UDP-GDH activity. UDP-xylose is a potent inhibitor of UDP-GDH but inhibitory concentrations of UDP-xylose could not be detected in cell extracts.
Biochem Mol Biol Int 1993 Aug
PMID:Serum stimulation of UDP-glucose dehydrogenase activity in Swiss 3T3 fibroblasts. 822 Feb 34


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>