Isoprenoid

Bài giảng Nguyên lý hoá sinh: Bài 6 cung cấp cho người đọc những kiến thức như: Lipid cấu trúc trong các màng; Lipid là các tín hiệu, cofactor và sắc tố; Thao tác với lipid. Mời các bạn cùng tham khảo!

151p bapnep06 27-02-2023 10 2   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

The 1-deoxyxylulose 5-phosphate reductoisomerase (DXR, EC1.1.1.267)catalyzes the conversionof 1-deoxy-D-xylulose 5-phosphate (DXP)into 2-C-methyl-D-erythritol 4-phos-phate (MEP). This transformation is a two-step process involving a rearrangement of DXP into the putative inter-mediate 2-C-methyl-D-erythrose 4-phosphate followed by a NADPH-dependent reduction of the latter aldehyde. By using [1-13 C]DXP as a substrate, the rearrangement of DXP into [5-13 C]2-C-methyl-D-erythrose 4-phosphate was shown to be NADPH dependent, although it does not involve a reduction step. ...

12p research12 23-04-2013 38 2   Download

The isoprenoid chain of ubiquinone (Q) is determined bytrans-polyprenyl diphosphate synthase in micro-organisms and presumably in mammals. Because mice and humans produce Q9 and Q10 , they are expected to pos-sess solanesyl and decaprenyl diphosphate synthases as the determining enzyme for a type of ubiquinone.

17p fptmusic 12-04-2013 27 3   Download

In the nonmevalonate pathway of isoprenoid biosynthesis, the conversion of 2C-methyl-D-erythritol 4-phosphate into its cyclic diphosphate proceeds via nucleotidyl intermediates and is catalyzed by the products of theispD,ispE andispF genes. An open reading frame of Campylobacter jejuni with similarity to theispDandispFgenes ofEscherichia coli was cloned into an expression vector directing the formation of a 42 kDa protein in a recombinantE. colistrain.

8p awards 05-04-2013 40 5   Download

An open reading frame (Acc. no. P50740) on theBacillus subtilis chromosome extending from bp 184 997–186 043 with similarity to theidi-2 gene ofStreptomycessp. CL190 specifying type II isopentenyl diphosphate isomerase was expressed in a recombinant Escherichia colistrain. The recombinant protein with a subunit mass of 39 kDa was purified to apparent homogeneity by column chromatog-raphy. The protein was shown to catalyse the conversion of dimethylallyl diphosphate into isopentenyl diphosphate and vice versa at rates of 0.23 and 0.

12p dell39 03-04-2013 44 4   Download

The carbon backbones of Z,E-mixed isoprenoids are synthesized by sequentialcis-condensation of isopentenyl diphosphate (IPP) and an allylic diphosphate through actions of a series of enzymes calledcis-prenyltrans-ferases. Recent molecular analyses of Micrococcus luteusB-P 26 undecapre-

11p dell39 27-03-2013 38 5   Download

The homodimeric 2C-methyl-d-erythritol 4-phosphate cytidylyltransferase contributes to the nonmevalonate pathway of isoprenoid biosynthesis. The crystal structure of the catalytic domain of the recombinant enzyme derived from the plant Arabidopsis thalianahas been solved by molecular replace-ment and refined to 2.0 A˚ resolution.

9p inspiron33 26-03-2013 35 5   Download

TheispC gene of Arabidopsis thalianawas expressed in pseudomature form without the putative plastid-targeting sequence in a recombinant Escherichia colistrain. The recombinant protein was purified by affinity chromatography and was shown to catalyze the formation of 2C-methyl-d-erythritol 4-phosphate from 1-deoxy-d-xylulose 5-phosphate at a rate of 5.6lmolÆmin )1 Æmg )1 (kcat 4.4 s )1 ). The Michaelis constants for 1-deoxy-d-xylulose 5-phosphate and the cosubstrate NADPH are 132 and 30lm, respectively. ...

13p inspiron33 25-03-2013 38 5   Download

2C-Methyl-d-erythritol-4-phosphate synthase, encoded by the ispC gene (also designated dxr), catalyzes the first committed step in the nonmevalo-nate isoprenoid biosynthetic pathway. The reaction involves the isomeriza-tion of 1-deoxy-d-xylulose 5-phosphate, giving a branched-chain aldose derivative that is subsequently reduced to 2C-methyl-d-erythritol 4-phos-phate.

14p galaxyss3 07-03-2013 47 4   Download

Ubiquinone is an essential factor for the electron transfer system and is also a known lipid antioxidant. The length of the ubiquinone isoprenoid side-chain differs amongst living organisms, with six isoprene units in the budding yeastSaccharomyces cerevisiae, eight units in Escherichia coliand 10 units in the fission yeast Schizosaccharomyces pombeand in humans.

16p galaxyss3 07-03-2013 54 4   Download

Human Brox is a newly identified 46 kDa protein that has a Bro1 domain-like sequence and a C-terminal thioester-linkage site of isoprenoid lipid (CAAX motif) (C standing for cysteine, A for generally aliphatic amino acid, and X for any amino acid).

11p media19 05-03-2013 30 3   Download

Proteins are covalently modified with a variety of lipids, including fatty acids, isoprenoids, and cholesterol. Lipid modifications play important roles in the localization and function of proteins. The focus of this review is S-palmitoylation, the reversible addition of palmitate and other long-chain fatty acids to proteins at cysteine residues in a variety of sequence contexts.

9p media19 04-03-2013 29 3   Download

In the apicoplast of apicomplexan parasites, plastidic-type ferredoxin and ferredoxin-NADP + reductase (FNR) form a short electron transport chain that provides reducing power for the synthesis of isoprenoid precursors. These proteins are attractive targets for the development of novel drugs against diseases such as malaria, toxoplasmosis, and coccidiosis.

12p vinaphone15 25-02-2013 32 2   Download

The ubiquinone coenzyme Q (CoQ) is synthesized in mitochondria with a large, hydrophobic isoprenoid side chain. It functions in mitochondrial res-piration as well as protecting membranes from oxidative damage. Yeast that cannot synthesize CoQ (DCoQ) are viable, but cannot grow on nonfer-mentable carbon sources, unless supplied with ubiquinone.

16p mobifone23 21-01-2013 24 4   Download

Tocopherol (tocos = con cháu, pherol = sinh ra) khá phổ biến ở cây xanh, rau xà lách, hạt ngũ cốc, dầu thực vật, gan bò, lòng đỏ trứng. Nhóm tocopherol gồm 8 hợp chất, bao gồm vòng 8 chromanol và một chuỗi bên isoprenoide Sản phẩm cuối cùng của quá trình sinh tổng hợp là -tocopherol (5,7,8-

4p pencil_7 12-10-2011 54 5   Download