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1.
Summary The degradation and conversion of -sitosterol to C-17-ketosteroids byNocardia sp. M 29 was studied. Maximal enzymatic activity was found after 24 h of incubation. Although the key enzymes involved in the decomposition of -sitosterol were inducible, no separate induction of side chain hydroxylase or 9-hydroxylase was possible. Inhibition of the steroid ring cleaving enzyme by ,-dipyridyl resulted in low yields of 4-androstene-3,17-dione and 1,4-androstadiene-3,17-dione (total yield 22%). Addition of lipophilic organic adsorbents (Amberlite XAD-2 and XAD-4) stimulated the 1,4-androstadiene-3,17-dione formation (maximal 50% within 120 h of incubation). Furthermore, 3-oxo-23,24-dinor-1,4-choladienic acid and 3-oxo-23,24-dinor-1,4-choladienic acid methyl ester were accumulated in the presence of Amberlite XAD-2 in moderate yields (total 11%).  相似文献   

2.
Mucor piriformis was used to study the mode of transformation of 16-dehydroprogesterone (I, pregna-4, 16-diene-3, 20-dione) and 17-hydroxyprogesterone (II, 17-hydroxypregn-4-ene-3, 20-dione). Biotransformation products formed from I were 14-hydroxypregna-4, 16-diene-3, 20-dione (Ia), 7, 14-dihydroxypregna-4, 16-diene-3, 20-dione (Ib), 3, 7, 14-trihydroxy-5-pregn-16-en-20-one (Ic), and 3, 7, 14-trihydroxy-5-pregn-16-en-20-one (Id). Metabolites Ic and Id appear to be hitherto unknown. Time-course studies suggested that the transformation is initiated by hydroxylation at the 14-position (Ia) followed by hydroxylation at the 7-position (Ib). Microsomes (105,000 g sediment) prepared from 16-dehydroprogesterone-induced cells hydroxylate I to its 14-hydroxy derivative (Ia) in the presence of NADPH. Incubation of Ia with the organism resulted in the formation of Ib, Ic and Id. Biotransformation products formed from compound II were 17, 20-dihydroxypregn-4-en-3-one (IIa), 7, 17-dihydroxypregn-4-ene-3, 20-dione (IIb), 6, 17, 20-trihydroxypregn-4-en-3-one (IIc) and 11, 17, 20-trihydroxypregn-4-en-3-one (IId). Time-course studies indicated that IIa is the initial product formed, which is further hydroxylated either at the 6 or 11 position. Incubation of IIa with the organism resulted in the formation of IIc and IId. Reduction of the 4-en-3-one system and 20-keto group has not been observed before in organisms of the order Mucorales. In addition, M. piriformis has been shown to carry out hydroxylation at the C-6, C-7, C-11 and C-14 positions in the steroid molecules tested.  相似文献   

3.
The taxonomic significance of the trunk limbs of the chydoridae (Cladocera)   总被引:1,自引:1,他引:0  
N. N. Smirnov 《Hydrobiologia》1966,27(3-4):337-343
Summary The differences in the structure of the trunk limbs allow to outline three sections of Chydoridae (see table I and fig. 1), coinciding with the sections distinguished according to the structure of the head pores.
Chydoridae (Cladocera)
Chydoridae (. ), , .
  相似文献   

4.
Summary 2-Amino-2-deoxyuridine reacts efficiently with nucleoside 5-phosphorimidazolides in aqueous solution. The dinucleoside monophosphate analogues were obtained in yields exceeding 80% under conditions in which little reaction occurs with the natural nucleosides.In a similar way, the 5-phosphorimidazolide of 2-amino-2-deoxyuridine undergoes self-condensation in aqueous solution to give a complex mixture of oligomers.The phosphoramidate bond in the dinucleoside monophosphate analogues is stable for several days at room temperature and pH 7. The mechanisms of their hydrolysis under acidic and alkaline conditions are described.Abbreviations A adenosine - C cytidine - G guanosine - U uridine - T thymidine - UN 3 2-azido-2-deoxyuridine - UNH 2 2-amino-2-deoxyuridine - ImpA adenosine 5-phosphorimidazolide - ImpU uridine 5-phosphorimidazolide - ImpUN 3 2-azido-2-deoxyuridine 5-phosphorimidazolide - ImpUNH 2 2-amino-2-deoxyuridine 5-phosphorimidazolide - pA adenosine 5-phosphate - pU uridine 5-phosphate - pUN 3 2-azido-2-deoxyuridine 5-phosphate - pUNH 2 2-amino-2-deoxyuridine 5-phosphate - UpA uridylyl-[35]-adenosine - UpU uridylyl-[35]-uridine - UNpA adenylyl-[52]-2-amino-2-deoxy-uridine - UNpU uridylyl-[52]-2-amino-2-deoxyuridine (pUN)n n=2,3,4 [25]-linked oligomers of pUNH 2 poly(A) polyadenylic acid - Im imidazole - MeIm l-methylimidazole  相似文献   

5.
Summary We report here a new human -globin gene rearrangement carrying the two normal, 2 and 1, and two hybrid, 1/2, globin genes in the order 5-2-1/2-1/2-1-3. Both the hybrid genes, subtyped with ApaI and RsaI restriction enzymes, were found to be of the uncommon anti 3.7 type II. The hybrid genes were expressed at the biosynthetic level and their interaction with the -thalassaemia IVS 1 nt 1 GA mutation caused thalassaemia intermedia. We also report a case of an -globin gene rearrangement in the twin of one of the -globin gene carriers; the duplicated gene was of the anti 4.2 type and was associated with the absence of RsaI polymorphism. The singular finding of an -anti 3.7 cluster with two identical rare hybrid genes suggests that the reciprocal unequal recombination causing the -globin gene rearrangements could be of the intra-chromosomal rather than the interchromosomal type.  相似文献   

6.
Progesterone biotransformation with recombinant yeasts Yarrowia lipolytica E129A15 and Saccharomyces cerevisiae GRF18/YEp5117 expressing bovine adrenocortical cytochrome P-45017 yielded 17-hydroxyprogesterone and two diols, 17,20- and 17,20-dihydroxypregn-4-en-3-ones. The oxidation of mixtures of the three steroids with chromic acid resulted in the cleavage of 17–20 bonds in the diols with the formation of androst-4-ene-3,17-dione. The biotransformation of pregn-4-ene-20-ol-3-one by means of Y. lipolytica E129A15 was accompanied by the following reactions: the primary oxidation of these compounds to progesterone and the subsequent successive reactions of 17-hydroxylation and 20- and 20-reduction. The results widen the possibilities of enzymatic and chemical modifications of steroids.  相似文献   

7.
A newly generated monoclonal antibody, YB-2, reacts simultaneously with Y (Fuc12Gal14[Fuc13]GlcNAc), Leb (fuc12Gal13[Fuc14]GlcNAc) and H type 2 (Fuc12Gal14GlcNAc) antigens (Jpn J Cancer Res 1993: 84; 641-8). Since these antigens have been reported to be expressed strongly in malignant colorectal tissues, we investigated the usefulness of this antibody as an immunochemical tool for diagnosis of colorectal cancer. The rate of positive staining with YB-2 antibody in colorectal carcinoma (n=101), adenoma (n=26) and normal tissues (n=25) was 95.0, 50.0 and 12.0%, respectively. The specimens with negative staining were restricted in Dukes' A patients but 75% of Dukes' C patients were strongly positive. The intensity of positive staining with YB-2 antibody was also significantly related to the clinico-pathological features such as the depth of invasion, metastasis, histological types and tumor location. Moreover, the 5-year survival in patients whose tumors were positive with YB-2 antibody was found to be significantly low. Therefore, YB-2 antibody could be useful for immunodiagnosis and, possibly, immunotherapy of colorectal carcinoma.  相似文献   

8.
Newborn rat adrenocortical cells were successfully cultured in a serum free carrier protein free medium (SPFM) by using -cyclodextrin as a cholesterol carrier and have expressed corticosteroid biosynthesis in this medium. A stable inclusion complex of cholesterol--cyclodextrin with a molar ratio of almost 1 was obtained for a 5 × 10–5 mol/1 -cyclodextrin concentration. Cell cultures incubated with [4-14C] cholesterol--cyclodextrin in SPFM produced, under ACTH stimulation, various 14C labeled steroids with a predominance of corticosterone and 18-hydroxy-11-deoxycorticosterone. As measured by gas chromatography and mass spectrometry, the ratio between corticosteroids (21-hydroxylated steroids) and 20-reduced steroids produced in SPFM with cholesterol--cyclodextrin was equal to 1.8. This corresponds to a value of 3.6 times higher than that found in the serum free medium with cholesterol-albumin. Consequently, the chemically defined SPFM with cholesterol--cyclodextrin used in this study is more suitable for corticosteroidogenesis by adrenal cells in culture than a serum free medium with cholesterol-albumin.Abbreviations -CD -cyclodextrin - ACTH adrenocorticotropic hormone - 20-dihydroprogesterone 20-hydroxy-4-pregnene-3-one - 11-hydroxy-20-dihydroprogesterone 11, 20-dihydroxy-4-pregnene-3-one - 11-hydroxyprogesterone 11-hydroxy-4-pregnene-3,20-dione - C--CD cholesterol--cyclodextrin complex - corticosterone 11,21-dihydroxy-4-pregnene-3,20-dione - deoxycorticosterone 21-hydroxy-4-pregnene-3,20-dione - 18-hydroxy-11-deoxycorticosterone 18,21-dihydroxy-4-pregnene-3,20-dione - 18-hydroxy-20-dihydroprogesterone 18-20-dihydroxy-4-pregnene-3-one - 18-hydroxyprogesterone 18-hydroxy4-pregnene-3,20-dione - progesterone 4-pregnene-3,20-dione - SFM-S serum-free medium - SPFM serum-free protein-free medium - SSM serum supplemented medium  相似文献   

9.
Summary Information regarding the relative levels of salt tolerance between cultivars of Kentucky bluegrass (Poa pratensis L.) is lacking. The objectives of this study were to 1) develop a simple, quick and sensitive method of screening turfgrass species for NaCl tolerance and 2) to compare the relative salt tolerance of five cultivars of Kentucky bluegrass (Ram I, Adelphi, Baron, Bensun, and Nassau) to other known salt tolerant turfgrass species such as alkalaigrass (Puccinellia distans (L.) Parl. cv. Fults) and two cultivars of red fescue (Festuca rubra L. Dawson, and Checker).Alkalaigrass and both cultivars of red fescue retained a high level of salt tolerance compared to the Kentucky bluegrass cultivars. Significant variability in salt tolerance was apparent among the Kentucky bluegrass cultivars with Adelphi and Ram I exhibiting the best overall tolerance.  相似文献   

10.
Summary Five subunits (-, -, -, - and -subunits) of the six -and -subunits) in the F1 portion (F1ATPase) of sweet potato (Ipomoea batatas) mitochondrial adenosine triphosphatase were isolated by an electrophoretic method. The - and -subunits were not distinguishable immunologically but showed completely different tryptic peptide maps, indicating that they were different molecular species. In vitro protein synthesis with isolated sweet potato root mitochondria produced only the -subunit when analyzed with anti-sweet potato F1ATPase antibody reacting with all the subunits except the -subunit. Sweet potato root poly(A)+RNA directed the synthesis of six polypeptides which were immunoprecipitated by the antibody: two of them immunologically related to the -subunit and the others to the - and -subunits. We conclude that the -subunit of the F1ATPase is synthesized only in the mitochondria and the -, - and -subunits are in the cytoplasm.  相似文献   

11.
Genetic linkage maps for two apple cultivars were constructed using AFLP and SSR markers and the pseudo-testcross mapping strategy. The F1-mapping population was produced by crossing the cultivar Braeburn to the cultivar Telamon and consisted of 257 individuals. Out of the 182 AFLP primer combinations screened, a total of 48 were selected. Using these, 463 AFLP markers segregating 1:1 in the progeny were identified, of which 231 were heterozygous in Telamon and 232 in Braeburn. Eighty-five AFLP markers present in both cultivars (3:1 segregation) were scored in the whole mapping population. Twenty-one SSR primer pairs were tested, which clearly screened 23 loci (some multi-locus markers). This resulted in the identification of 3 loci heterozygous only in Telamon (1:2:1), 5 loci heterozygous only in Braeburn (1:2:1) and 15 loci which were heterozygous in both cultivars (1:1:1:1). Two linkage maps were produced. The Telamon map comprised 259 markers (242 AFLPs and 17 SSRs) divided into 17 linkage groups. The total map length was 1039 cM with a marker density of 4.0 cM. At = 0.05, 8.9% of the mapped loci showed distorted segregation. The Braeburn map consisted of 264 markers (245 AFLPs and 19 SSRs) mapped on 17 linkage groups and spanning 1245 cM. The average distance between two markers was 4.7 cM and segregation distortion was observed for 18.6% of the mapped markers ( = 0.05). Fourty-six markers common to both maps (32 AFLPs and 14 SSRs) allowed the identification of 16 homologous linkage groups. The seventeenth pair of homologous linkage groups from Telamon and Braeburn was identified by 2 SSR markers which were in common to the genetic linkage maps of Fiesta and Discovery, two other apple cultivars.  相似文献   

12.
Summary Human and rabbit masticatory muscles were analyzed immuno-and enzyme-histochemically using antibodies specific to cardiac , slow and fast myosin heavy chain isoforms. In human masseter, temporalis, and lateral pterygoid muscle cardiac myosin heavy chain is found in fibres that contain either fast, or fast and slow myosin heavy chain. In rabbit masseter, temporalis and digastric muscles, fibres are present that express cardiac myosin heavy chain either exclusively, or concomitantly with slow myosin heavy chain or fast myosin heavy chain. Our results demonstrate a much broader distribution of cardiac myosin heavy chain than hitherto recognized and these might explain in part the specific characteristics of masticatory muscles. The cardiac myosin heavy chain is only found in skeletal muscles originating from the cranial part of the embryo (including the heart muscle) suggesting that its expression might be determined by the developmental history of these muscles.  相似文献   

13.
Summary The effect of the msm1 cytoplasm of barley (Hordeum vulgare L.) on kernel protein and lysine was studied using the near-isogenic, unrestored derivatives of seven barley varieties. With normal lysine varieties, Adorra, Bomi, CI 4362, and Hankkija's Eero, the msm1 cytoplasm produced an average of one percentage point more protein than did the normal cytoplasm of the same varieties. There was no difference between the two cytoplasms with respect to their effect on the lysine content. With high lysine varieties, Bomi Risø mutant 13, Bomi Risø mutant 1508, and CI 3947, msm1 produced almost one percentage point more protein but protein with a somewhat decreased lysine content.Induced partial spike fertility in normal Adorra was found to be associated with lysine in meal (r=–0.999), with protein in meal (r=–0.984), and with lysine in protein (r=0.941). Removal of the spikes on the secondary tillers affected both the protein and its lysine content. It is suggested that good spike fertility is an important pre-requisite when selecting high lysine and/or high protein segregants or mutants.  相似文献   

14.
Holophosphorylase kinase was digested with Glu-C specific protease; from the peptide mixture calmodulin binding peptides were isolated by affinity chromatography and identified by N-terminal sequence analysis. Two peptides originating from the subunit, having a high tendency to form a positively charged amphiphilic helix and containing tryptophane, were synthesized. Additionally, a homologous region of the subunit and a peptide from the subunit present in a region deleted in the isoform were also selected for synthesis. Binding stoichiometry and affinity were determined by following the enhancement in tryptophane fluorescence occurring upon 1:1 complex formation between these peptides and calmodulin. Finally, Ca2+ binding to calmodulin in presence of peptides was measured. By this way, the peptides 542–566, 547–571, 660–677 and 597–614 have been found to bind specifically to calmodulin.Together with previously predicted and synthesized calmodulin binding peptides four calmodulin binding regions have been characterized on each the and subunits. It can be concluded that endogenous calmodulin can bind to two calmodulin binding regions in as well as to two regions in and . Exogenous calmodulin can bind to two regions in and in . A binding stoichiometry of 0.8mol of calmodulin/ protomer of phosphorylase kinase has been determined by inhibiting the ubiquitination of calmodulin with phosphorylase kinase. Phosphorylase kinase is half maximally activated by 23nM calmodulin which is in the affinity range of calmodulin binding peptides from to calmodulin. Therefore, binding of exogenous calmodulin to activates the enzyme. A model for switching endogenous calmodulin between , and and modulation of ATP binding to as well as Mg2+/ADP binding to by calmodulin is presented.  相似文献   

15.
The mechanism for synthesis of monounsaturated fatty acids under aerobic and anaerobic conditions was studied in the facultative anaerobic cyanobacterium, Oscillatoria limnetica. The hexadecenoic acid (C161) of aerobically grown O. limnetica was shown to contain both the 7 (79%) and 9 (21%) isomers, while the octadecenoic (C181) acid was entirely the 9 acid. Incorporation of [2-14C] acetate into the fatty acids under aerobic conditions resulted in synthesis of the 7 and 9 C161 and the 9 C181. Synthesis of unsaturated fatty acids in the presence of DCMU required sulfide. Anaerobic incubations in the presence of DCMU and sulfide (less than 0.003% atmospheric oxygen) resulted in a two-fold increase in monounsaturated fatty acids of both 7 and 9 C161 and 9 and 11 C181. The synthesis of these isomers is characteristic of a bacterialtype, anaerobic pathway.Abbreviations DCMU 3(3,4-dichlorophenyl)-1,1-dimethylurea - MFA monounsaturated fatty acid  相似文献   

16.
Oxidative injury and antioxidant responses were investigated in two banana genotypes (Musa AAA Berangan and Musa AA Mas) subjected to 40 % PEG-induced water stress. PEG treatment resulted in oxidative injury, as expressed in increased lipid peroxidation and reduced membrane stability index, in both cultivars; however, greater oxidative injury was detected in Mas. Under PEG treatment, catalase activity and glutathione reductase activity were enhanced in both cultivars, but were higher in Mas. Ascorbate peroxidase activity was enhanced in Berangan under water stress, but was unaffected in Mas. Meanwhile, superoxide dismutase activity was inhibited in both cultivars under water stress, but higher activity was detected in Berangan. Higher ascorbate peroxidase and superoxide dismutase activities were associated with greater protection against water stress-induced oxidative injury.  相似文献   

17.
Ionic relations of aeroponically-grown olive genotypes,during salt stress   总被引:1,自引:1,他引:0  
Two olive (Olea europaea L.) genotypes, Frantoio and Leccino, were exposed to increasing concentrations of NaCl (0-30-60-120 mM) in an aeroponic cultivation system for 60 days. Dry weights and sodium and potassium contents of apical and basal leaves, new and old wood, and roots were measured to determine Na uptake rate, Na translocation rate and K-Na selectivity ratio (SK,Na). Frantoio showed a higher salt resistance than Leccino. Frantoio and Leccino had a similar Na uptake rate, but largely differed for Na translocation to the shoot. Furthermore Frantoio exhibited a higher K-Na selectivity than Leccino at both whole plant level and above all at the level of shoot system. Resistance mechanism of Frantoio is probably related to Na esclusion by roots and to the ability to maintain an appropriate K/Na ratio in actively growing tissues.Research supported by National Research Council of Italy, Special project RAISA.  相似文献   

18.
Summary The carotenoid pigments of the myxobacterium Sorangium compositum were analyzed by chromatographical and chemical techniques and by visible, infra red, and mass spectroscopy. Besides -carotene, neurosporene, torulene, lycopene, and 1,2-dihydro-1-hydroxy--carotene, four new carotenoid glycosides were found. These pigments were identified as 1,2-dihydro-1-hydroxy-torulene glucoside ester (I), 1,2-dihydro-3,1-dihydroxy-torulene glucoside ester (III), 1,2-dihydro-1-hydroxy-torulene rhamnoside (II), and 1,2-dihydro-3,1-dihydroxytorulene rhamnoside (IV).Fifth communication on the carotenoids of myxobacteria. Fourth communication see Arch. Mikrobiol. 76, 364–380 (1971).  相似文献   

19.
4-Methylumbelliferyl 6-O-benzyl--d-lactoside (6Bn-MU-Lac) and some related compounds were synthesizedvia different selective reactions including phase-transfer glycosylation. Their suitability as substrates for a fluorometric assay of ceramide glycanase (CGase) was evaluated. Among others, the 6Bn-MU-Lac, which is resistant to exogalactosidase, was found to be a suitable substrate for routine assay of the CGase activity. For American leech CGase, theK m value is 0.232 mM at pH 5. Abbreviations: CGase, ceramide glycanase; Gal, galactose; Glc, Glucose; Lac, lactose; MU, 4-methylumbelliferone; MU-Lac, 4-methylumbelliferyl -d-lactoside; bBn-Lac, 6-O-benzyl-lactose; 6Bn-MU-Lac, 4-methylumbelliferyl 6-Obenzyl--d-lactoside; 46Bd-MU-Lac, 4-methylumbelliferyl 4,6-O-benzylidene--d-lactoside; MU-Cel, 4-methylumbellifery -d-cellobioside; 46Bd-MU-Cel, 4-methylumbelliferyl 4,6-O-benzylidene--d-cellobioside; TLC, thin layer chromatography;1H-NMR, proton nuclear magnetic resonance; GSL, glycosphingolipids; CSA, 10-camphorsulfonic acid. See Scheme 1 for chemical structures.  相似文献   

20.
A linkage map with RFLP and isozyme markers for almond   总被引:12,自引:0,他引:12  
Inheritance and linkage studies were conducted with seven isozyme genes and 120 RFLPs in the F1 progeny of a cross between almond cultivars Ferragnes and Tuono. RFLPs were detected using 57 genomic and 43 cDNA almond clones. Eight of the cDNA probes corresponded to known genes (extensin, prunin (2), -tubulin, endopolygalacturonase, oleosin, actin depolymerizing factor and phosphoglyceromutase). Single-copy clones were found more frequently in the cDNA (65%) than in the genomic libraries (26%). Two maps were elaborated, one with the 93 loci heterozygous in Ferragnes and another with the 69 loci heterozygous in Tuono. Thirty-five loci were heterozygous in both parents and were used as bridges between both maps. Most of the segregations (91%) were of the 11 or 1111 types, and data were analyzed as if they derived from two backcross populations. Eight linkage groups covering 393 cM in Ferragnes and 394 in Tuono were found for each map. None of the loci examined in either map was found to be unlinked. Distorted segregation ratios were mainly concentrated in two linkage groups of the Ferragnes map.  相似文献   

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