Methyltransferases

Luận văn nghiên cứu lý thuyết về đặc điểm trình tự gen và protein CoOMT; tạo dòng tế bào vi khuẩn tái tổ hợp mang gen nhân tạo CoOMT; thiết kế vector chuyển gen pBI121-1113 và tạo chủng Agrobacterium tumefaciens tái tổ hợp mang gen CoOMT. Mời các bạn cùng tham khảo nội dung chi tiết.

61p beloveinhouse03 22-08-2021 28 4   Download

To assess the frequency allele and genotypic distribution of polymorphism rs165599 in catechol-O-methyltransferase in Kinh ethnic-patients with schizophrenia. Subjects and methods: A case-control study consisted of 227 schizophrenic patients and 92 healthy controls in the Kinh ethnic. The rs165599 was genotyped by PCR-RFLP and statistical analysis was performed by Chi-Square test. Results: The frequency of allele A and G in schizophrenic patients were 72.36% and 69.94%, respectively. The frequency of allele A and G in healthy controls were 27.64% and 30.06%, respectively (p > 0.05).

6p chauchaungayxua1 02-12-2019 28 3   Download

The Sp family is a family of transcription factors that bind to cis-elements in the promoter regions of various genes. Regulation of transcription by Sp proteins is based on interactions between a GC-rich binding site (GGGCGG) in DNA and C-terminal zinc finger motifs in the proteins. In this study, we characterized the GC-rich promoter of the gene for the DNA methyltransferase (Dnmt1) that is responsible for methylation of cytosine residues in mammals and plays a role in gene silencing.

10p system191 01-06-2013 38 4   Download

The isoprenoid methyl farnesoate (MF) has been implicated in the regulation of crustacean development and reproduction in conjunction with eyestalk molt inhibiting hormones and ecdysteroids. Farnesoic acid O-methyltransferase (FAMeT) catalyzes the methylation of farnesoic acid (FA) to produce MF in the terminal step of MF synthesis. We have previously cloned and characterized the shrimp FAMeT. In the present study, recombinant FAMeT (rFAMeT) was produced for bioassay and antiserum generation.

9p research12 01-06-2013 41 3   Download

Nuclear receptors (NRs) are ligand-regulated, DNA-binding transcription factors that function in the chromatin environment of the nucleus to alter the expression of subsets of hormone-responsive genes. It is clear that chromatin, rather than being a passive player, has a profound effect on both transcriptional repression and activation mediated by NRs.

9p research12 01-06-2013 32 2   Download

Methanol:coenzyme M methyltransferase from methanogenic archaea is a cobalamin-dependent enzyme composed of three different subunits: MtaA, MtaB and MtaC. MtaA is a zinc protein that catalyzes the methylation of coenzyme M (HS-CoM) with methylcob(III)alamin. We report zinc XAFS (X-ray absorption fine structure) results indicating that, in the absence of coenzyme M, zinc is probably coordinated by a single sulfur ligand and three oxygen or nitrogen ligands. In the presence of coenzyme M, one (N/O)-ligand was replaced by sulfur, most likely due to ligation of the thiol group of coenzyme M....

7p research12 01-06-2013 52 5   Download

The ÔMediterraneanÕ variant of glucose-6-phosphate dehydrogenase (G6PD) deficiency is due to the C563CT point mutation, leading to replacement of Ser with Phe at position 188, resulting in acute haemolysis triggered by oxidants. Previous work has shown increased formation of altered aspartate residues in membrane proteins during cell ageing and in response to oxidative stress in normal erythrocytes. These abnormal residues are specifically recognized by the repair enzyme L-isoaspartate (D-aspartate) protein O-methyltransferase (PCMT; EC 2.1.1.77). ...

8p research12 01-06-2013 38 4   Download

DNA cytosine methyltransferaseMspI(M.MspI) must require a different type of interaction of protein with DNA from other bacterial DNA cytosine methyltransferases (m5C-MTases) to evoke the topoisomerase activity that it possesses in addition toDNA-methylation ability. Thismay require a different structural organization in the solution phase from the reported consensus structural arrangement for m5C-MTases.

7p research12 29-04-2013 45 3   Download

Chlorophyll biosynthesis requires a metabolic dialog between the chloroplast envelope and thylakoids where biosynthetic activities are localized. Here, we report the ®rst plant S-adenosyl-L-methionine:Mg-protoporphyrin IX methyltransferase (MgPIXMT) sequence identi®ed in the Arabidopsisgenome owing to its similarity with the Synechocystis sp.

9p research12 29-04-2013 39 3   Download

To identify all of theO-methyltransferase genes involved in isoquinolinealkaloidbiosynthesis inCoptis japonicacells,we sequenced 1014 cDNAclones isolated from high-alkaloid-producing cultured cells ofC. japonica.Amongthem,we found all three reported O-methyltransferases and an O-methyltransferase-likecDNAclone (CJEST64).This cDNA was quite similar toS-adenosyl-L-methionine:coclaurine 6-O-methyltransferase and S-adenosyl-L-methionine:iso-flavone 7-O-methyltransferase.

9p tumor12 22-04-2013 26 3   Download

Dnmt3a is ade novoDNA methyltransferase that modifies unmethylated DNA. In contrast Dnmt1 shows high pre-ference for hemimethylatedDNA. However, Dnmt1 can be activated for themethylationof unmodifiedDNA.We show here that the Dnmt3a andDnmt1 DNA methyltransferases functionally cooperate in de novo methylation of DNA, because a fivefold stimulation of methylation activity is observed if both enzymes are present.

4p tumor12 22-04-2013 34 2   Download

A new enzyme,S-adenosyl-L-methionine:flavonoid 4¢-O-methyltransferase (EC 2.1.1.-)(F 4¢-OMT), has been puri-fied 1 399-fold from the tissues of carnation (Dianthus caryophyllus L). The enzyme, with a molecular mass of 43–45 kDa and a pI of 4.15, specifically methylates the hydroxysubstituent in4¢-positionof theflavones, flavanones and isoflavones in the presence ofS-adenosyl-L-methionine. A high affinity for the flavone kaempferol was observed (Km¼1.7lM;Vmax¼95.2lmolÆmin )1 Æmg )1 ), while other 4¢-hydroxylated flavonoids proved likewise to be suitable substrates....

10p tumor12 20-04-2013 43 2   Download

Tocopherols are essential micronutrients in human and animal nutrition due to their function as lipophilic anti-oxidants. Theyare exclusively synthesizedbyphotosynthetic organisms including higher plants. Despite the attributed beneficial health effects and many industrial applications, research on the tocopherol biosynthetic pathway and its regulation inplants is still limited.

9p tumor12 20-04-2013 40 4   Download

Purified recombinant proteins fromSynechocystisPCC6803 were used to show that the magnesium chelatase ChlH subunit stimulates magnesium protoporphyrin methyltransferase (ChlM) activity. Steady-state kinetics demonstrate that ChlH does not significantly alter theKmfor the tetrapyr-role substrate. However, quenched-flow analysis reveals that ChlH dramat-ically accelerates the formation and breakdown of an intermediate in the catalytic cycle of ChlM.

8p fptmusic 12-04-2013 45 2   Download

EcoRII DNA methyltransferase (M.EcoRII) recognizes the 5¢…CC*T/AGG…3¢ DNA sequence and catalyzes the transfer of the methyl group fromS-adenosyl-L-methionine to the C5 position of the inner cytosine residue (C*). Here, we study themechanismof inhibitionofM.EcoRII byDNA containing 2-pyrimidinone, a cytosine analogue lacking an NH2 group at the C4 position of the pyrimidine ring. Also, DNA containing 2-pyrimidinone was used for probing contacts ofM.EcoRII with functional groups of pyrimidine bases of the recognition sequence....

9p dell39 03-04-2013 35 4   Download

Plants belonging to the Apiaceae or Rutaceae accumulate methoxylated psoralens, such as bergapten or xanthotoxin, as the final products of their furanocoumarin biosynthesis, and the rate of accumulationdepends on environmental and other cues. DistinctO-methyltransferase activities had been reported to methylate bergaptol to bergapten and xantho-toxol to xanthotoxin, from induced cell cultures of Ruta graveolens,Petroselinum crispumandAmmi majus. Bergap-tol 5-O-methyltransferase (BMT) cDNA was cloned from dark-grownAmmi majusL. cells treatedwith a crude fungal elicitor. ...

9p dell39 03-04-2013 53 3   Download

Glucocorticoid receptor-interacting protein 1 (GRIP1), a p160 family nuc-lear receptor co-activator, possesses at least two autonomous activation domains (AD1 andAD2) in the C-terminal region.AD1 activity appears to be mediated by CBP⁄p300, whereasAD2 activity is apparently mediated through co-activator-associated arginine methyltransferase 1 (CARM1).

12p inspiron33 26-03-2013 33 3   Download

During anaerobic cobalamin (vitamin B12) biosynthesis, CbiL catalyzes methylation at the C-20 position of a cyclic tetrapyrrole ring usingS-aden-osylmethionine as a methyl group source. This methylation is a key modifi-cation for the ring contraction process, by which a porphyrin-type tetrapyrrole ring is converted to a corrin ring through elimination of the modified C-20 and direct bonding of C-1 to C-19.

11p inspiron33 23-03-2013 35 2   Download

The biologically most significant genotoxic metabolite of the environmental pollutant benzo[a]pyrene (B[a]P), (+)-7R,8S-diol 9S,10R-epoxide, reacts chemically with guanine in DNA, resulting in the predominant formation of (+)-trans-B[a]P-N 2 -dG and, to a lesser extent, (+)-cis-B[a]P-N 2 -dG adducts.

14p galaxyss3 19-03-2013 30 3   Download

Juvenile hormone controls the timing of insect metamorphosis. As a final step of juvenile hormone biosynthesis, juvenile hormone acid O-methyl-transferase (JHAMT) transfers the methyl group from S-adenosyl-l-methi-onine to the carboxyl group of farnesoic acid and juvenile hormone acid.

13p galaxyss3 07-03-2013 30 4   Download