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151.
Seminal vesicle secretory protein IV of a mouse has been isolated, and the cDNA coding for its mRNA has been cloned and sequenced. The 556-nucleotides encode 16 amino acid signal peptides and 92 residues of mature protein. Considerable homology between mouse and rat SVS IV cDNA was found. In the leader peptide and 3'-noncoding region there is 92% and 85% homology, respectively. The other regional homologies are 86% for the first 12, 68.5% for the last 35, and 40% for the middle 44 amino acids. The expression of mouse SVS IV mRNA is under the control of androgen. Administration of testosterone to castrated mice resulted in induction of the mRNA level to 50% of the mature male in 96 h of hormone treatment. Secretion of the protein after testosterone injection follows a similar pattern.  相似文献   
152.
D Chen  K T Yue  C Martin  K W Rhee  D Sloan  R Callender 《Biochemistry》1987,26(15):4776-4784
We report the Raman spectra of reduced and oxidized nicotinamide adenine dinucleotide (NADH and NAD+, respectively) and adenosine 5'-diphosphate ribose (ADPR) when bound to the coenzyme site of liver alcohol dehydrogenase (LADH). The bound NADH spectrum is calculated by taking the classical Raman difference spectrum of the binary complex, LADH/NADH, with that of LADH. We have investigated how the bound NADH spectrum is affected when the ternary complexes with inhibitors are formed with dimethyl sulfoxide (Me2SO) or isobutyramide (IBA), i.e., LADH/NADH/Me2SO or LADH/NADH/IBA. Similarly, the difference spectra of LADH/NAD+/pyrazole or LADH/ADPR with LADH are calculated. The magnitude of these difference spectra is on the order of a few percent of the protein Raman spectrum. We report and discuss the experimental configuration and control procedures we use in reliably calculating such small difference signals. These sensitive difference techniques could be applied to a large number of problems where the classical Raman spectrum of a "small" molecule, like adenine, bound to the active site of a protein is of interest. The spectrum of bound ADPR allows an assignment of the bands of the bound NADH and NAD+ spectra to normal coordinates located primarily on either the nicotinamide or the adenine moiety. By comparing the spectra of the bound coenzymes with model compound data and through the use of deuterated compounds, we confirm and characterize how the adenine moiety is involved in coenzyme binding and discuss the validity of the suggestion that the adenine ring is protonated upon binding. The nicotinamide moiety of NADH shows significant molecular changes upon binding.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
153.
K X Chen  N Gresh    B Pullman 《Nucleic acids research》1987,15(5):2175-2189
Theoretical computations are performed of the intercalative binding of the neocarzinostatin chromophore (NCS) with the double-stranded oligonucleotides d(CGCG)2, d(GCGC)2, d(TATA)2 and d(ATAT)2. Minor groove binding is preferred over major groove binding. It is found that the long axis of the stacked naphtoate ring lies approximately parallel to the long axis of the base pairs of the intercalation site. The galactosamine ammonium group interacts with specific sites of the groove (O2/N3 of bases 2 and O1' of sugar S3), whereas the dodecadyine ring system wraps around the groove towards the backbone. An overall AT versus GC preference is derived. Intercalation in a central purine-(3', 5')-pyrimidine sequence appears to be preferred over that in a central pyrimidine-(3', 5')-purine sequence.  相似文献   
154.
梁雁冰  陈永强  黄步汉   《广西植物》1987,(3):271-273
嘉兰原属热带性地区的植物,但从云南南部引种到广州地区种植。表现生长发育良好,且其秋水仙碱含量高达0.40—0.45%。是一种有推广种植价植的药用植物。  相似文献   
155.
Aqueous extract prepared from garlic bulbs markedly suppressed the mutagenesis in both E. coli WP2 trp- and E. coli WP2 trp- uvrA- induced by 4-nitroquinoline 1-oxide (4NQO), but not that induced by UV. Cellular toxicity, inhibition of the expression of the Trp+ phenotype and delay of the first cell division after 4NQO treatment were not observed in the presence of the extract. Since the extract showed identical antimutagenic effects against 4NQO in both test strains but no effect on the mutagenesis of UV, it seems that the extract might act by inactivating the electrophilic group(s) of 4NQO or inhibiting its metabolic activation.  相似文献   
156.
Chou M  Chen YM  Lin CY 《Plant physiology》1989,89(2):617-621
Mitochondria isolated from 2-day-old etiolated soybean (Glycine max) seedlings which had been subjected to various heat shock treatments, i.e. (A) 28°C (2 h), (B) 38°C (2 h), (C) 38°C (2 h)-42.5°C (0.5 h), and (D) 38°C (2 h)-42.5°C (0.5 h)-28°C (4 h), were monitored for O2 uptake using an oxygen electrode. Mitochondria isolated after all four heat shock treatments were active in O2 consumption at 28°C in response to succinate and ADP (derived P/O ratios were 1.6, 1.7, 1.3, and 1.3, respectively.) The mitochondria from all four treatments were also active in O2 uptake at 42.5°C. However, only mitochondria isolated after treatment (C) were tightly coupling at 42.5°C (derived ADP/O ratio was about 1.4). Combined with our earlier findings on the subcellular localization of heat shock proteins, our present data demonstrate that association of heat shock proteins with mitochondria by treatment (C) enables them to phosphorylate at 42.5°C (i.e. they become thermotolerant). Isolated mitochondria from treatment (C) and treatment (A) were compared by electron microscopy. They appeared to be very similar and no significant ultrastructural differences were noted.  相似文献   
157.
Two NADP-isocitrate dehydrogenase isoenzymes designated as NADP-IDH1 and NADP-IDH2 (EC 1.1.1.42) were identified in pea (Pisum sativum) leaf extracts by diethylaminoethylcellulose chromatography. The predominant form was found to be NADP-IDH1 while NADP-IDH2 represented only about 4% of the total leaf enzyme activity. These enzymes share few common epitopes as NADP-IDH2 was poorly recognized by the specific polyclonal antibodies raised against NADP-IDH1, and as a consequence NADP-IDH2 does not result from a post-translational modification of NADP-IDH1. Subcellular fractionation and isolation of chloroplasts through a Percoll gradient, followed by the identification of the associated enzymes, showed that NADP-IDH1 is restricted to the cytosol and NADP-IDH2 to the chloroplasts. Compared with the cytosolic isoenzyme, NADP-IDH2 was more thermolabile and exhibited a lower optimum pH. The data reported in this paper constitute the first report that the chloroplastic NADP-IDH and the cytosolic NADP-IDH are two distinct isoenzymes. The possible functions of the two isoenzymes are discussed.Abbreviations BSA bovine serum albumin - DEAE diethylaminoethyl - NADP-IDH NADP-isocitrate dehydrogenase - NADP-IDH1 cytosolic NADP-IDH - NADP-IDH2 chloroplastic NADP-IDH  相似文献   
158.
Historically, restoration of hand function following multiple digital amputation has been unsatisfactory. The evolution of digital reconstruction with toe transfer has enabled surgeons to reestablish prehension in these severely injured hands. A 4-year experience with 26 consecutive combined second and third toe transfers to replace missing adjacent fingers was reviewed in order to delineate the indications and technical considerations and to emphasize prevention of donor-site complications. Combined second and third toe transfer is reserved for adjacent finger amputations proximal to the digital web space with remaining fingers no longer than the small finger. Radial amputations are replaced with contralateral combined toe units, while ipsilateral toes are more ideal for ulnar amputations. Limited dorsal and plantar skin flaps extending only to the midpoint of the first and third digital web spaces allow for direct donor-site closure and uncomplicated healing. Maintenance of the plantar metatarsal arch by avoiding metatarsal shaft osteotomies or bone grafting-shortened metatarsals eliminates potential gait disturbances. When properly applied in selected patients, this single-stage microsurgical procedure can restore prehensile function, improve the appearance of the hand with multiple digital amputations, and preserve near-normal donor-foot function.  相似文献   
159.
More monensin-sensitive, ammonia-producing bacteria from the rumen   总被引:4,自引:0,他引:4  
Two monensin-sensitive bacteria which utilized carbohydrates poorly and grew rapidly on amino acids were isolated from the bovine rumen. The short rods (strain SR) fermented arginine, serine, lysine, glutamine, and threonine rapidly (greater than 158 nmol/mg of protein per h) and grew faster on casein digest containing short peptides than on free amino acids ().34 versus 0.29 h(-1)). Gelatin hydrolysate, an amino acid source containing an abundance of long peptides, was unable to support growth or ammonia production, but there was a large increase in ammonia production if strain SR was cocultured with peptidase-producing ruminal bacteria (Bacteroides ruminicola or Streptococcus bovis). Cocultures showed no synergism with short peptides. Strain SR washed out of continuous culture ().1 h(-1)) at pH 5.9. The irregularly shaped organisms (strain F) deaminated glutamine, histidine, glutamate, and serine rapidly (greater than 137 nmol/mg of protein per min) and grew faster on free amino acids than on short peptides ().43 versus 0.21 h(-1)). When strain F was provided with casein or gelatin hydrolysate and cocultured with peptidase-producing bacteria, there was a more than additive increase in ammonia production. Strain F grew in continuous culture (0.1 h(-1)) when the pH was as low as 5.3. The irregularly shaped cells and short rods were present at less than 10(9)/ml in vivo, but they ahd very high specific activities of ammonia production (greater than 310 nmol of ammonia/mg of protein per min) and could play an important role in ruminal amino acid fermentation.  相似文献   
160.
Summary The production of 9-cis-1, 18-octadecenedioic acid from different substrates by the mutant S76 of Candida tropicalis was studied. It was found that the mutant could convert oleyl alcohol, oleic acid, and methyl oleate to 9-cis-1, 18-octadecenedioic acid through either the diterminal oxidation of the alcohol or the -oxidation of the terminal methyl group of the mono acid. The geometric configuration of the product was identified by different analytical methods. The results demonstrated that no change in the geometric configuration of molecular structure happened during the bioconversion of such unsaturated substrates to 9-dioic acid. To enhance the production of this dioic acid in the medium, calcium carbonate was added as a trapping agent. The IR spectrum, 1H NMR and 13C-satellite spectra of this compound were presented.Dedicated to Professor Dr. K. Esser on the occasion of his 65th birthday  相似文献   
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