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91.
Dormant, intact Avena fatua L. (wild oat) seeds germinate poorly at 20 °C. Removing the hulls slightly increased germination. Treatment with smoke solutions
increased the germination of both intact seeds and caryopses. Exogenous GA3, alone or in the presence of smoke solution, increased the germination of caryopses, while ACC shows a tendency to increase
germination of caryopses only when applied in combination with smoke solution. Results suggest that GA3 and ethylene, but not smoke solutions, are involved in the regulation of α-amylase activity during germination. However,
the participation of smoke solutions in the control of ACC oxidase activity cannot be excluded. 相似文献
92.
Hierarchical cluster analysis and principal components have been used to provide a more detailed separation of the collagens into natural taxonomic groupings than previously obtained. These groups strongly reflect the evolutionary development of collagen. The first component separates land- from sea-based animals, primarily based on the hydroxylation of lysine and proline, indicating that control of hydroxylation, a post-translational event, has exerted a dominant influence during evolutionary adaptation. The power of the technique is illustrated by the ability to partially separate the evolutionarily closely related main homothermic species. Furthermore, the genetically different fibrous collagens, Types I and III, are well separated from basement membrane Type IV collagen and the filamentous collagens. The technique could, therefore, in addition to providing a taxonomic grouping, classify any new collagen and provide clues to its evolutionary development. 相似文献
93.
Isabella Y. Kong Stephanie Trezise Amanda Light Izabela Todorovski Gisela Mir Arnau Sreeja Gadipally David Yoannidis Kaylene J. Simpson Xueyi Dong Lachlan Whitehead Jessica C. Tempany Anthony J. Farchione Amania A. Sheikh Joanna R. Groom Kelly L. Rogers Marco J. Herold Vanessa L. Bryant Matthew E. Ritchie Simon N. Willis Ricky W. Johnstone Philip D. Hodgkin Stephen L. Nutt Stephin J. Vervoort Edwin D. Hawkins 《Cell death and differentiation》2022,29(12):2519
94.
Human apolipoprotein A-I isoprotein metabolism: proapoA-I conversion to mature apoA-I 总被引:3,自引:0,他引:3
D Bojanovski R E Gregg G Ghiselli E J Schaefer J A Light H B Brewer 《Journal of lipid research》1985,26(2):185-193
ProapoA-I (apoA-i+2 isoform) is the major apoA-I isoprotein secreted by the liver and intestine; however, it is a minor isoprotein in plasma and lymph where the major A-I apo-lipoprotein is mature apoA-I (apoA-I0, apoA-I-1, and apoA-I-2 isoforms). In the present report we provide evidence that apoA-I is rapidly and quantitatively converted to mature apoA-I, and the mature apoA-I isoforms are catabolized at equal rates. In these studies, human proapoA-I was isolated from thoracic duct chylomicrons collected during active fat absorption and mature apoA-I was isolated from plasma high density lipoproteins. The isolated lipoproteins were delipidated, fractionated by gel permeation chromatography, and the individual apoA-I isoforms were separated by preparative isoelectrofocusing. The metabolism of apoA-I isoproteins was studied in normal volunteers (N = 6) in a metabolic ward. In the first study proapoA-I and mature apoA-I (apoA-I0 isoform) were injected simultaneously into two normal subjects and the conversion of proapoA-I to mature apoA-I and the decay of radioactivity were followed in plasma and HDL over a 14-day period. ProapoA-I was rapidly and completely converted to mature apoA-I with a fractional rate of conversion of 4.0 pools/day. The average residence times of proapoA-I and mature apoA-I were 0.23 and 6.5 days, respectively. The mature apoA-I derived from proapoA-I had a residence time which was the same as the injected mature apoA-I.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
95.
D R Light M S Dennis I J Forsythe C C Liu D W Green D A Kratzer B V Plapp 《The Journal of biological chemistry》1992,267(18):12592-12599
The cDNA for the alpha-isoenzyme from rhesus monkey (Macaca mulatta) liver was cloned and expressed in yeast. The alpha-isoenzymes of human and monkey liver alcohol dehydrogenase differ from the other human and horse liver enzymes in having Met57, Ala93, and Val116 instead of Leu57, Phe93, and Leu116 in the substrate binding pocket and Gly47 instead of Arg47 near the pyrophosphate moiety of the coenzyme. The effects of these differences on the kinetic mechanism, substrate specificity, and coenzyme binding were studied with the purified, recombinant monkey alpha-isoenzyme (MmADH alpha) and mutated enzymes with Gly47 substituted with His or Arg. The mechanism appears to be random for the binding of NAD+ and ethanol and ordered for NADH and acetaldehyde, with formation of a dead-end enzyme-NADH-ethanol complex. MmADH alpha reacts 130-fold slower (V/K) with ethanol and 3-25-fold slower with 2-methyl alcohols but 20-fold faster with cyclohexanol, as compared with horse (Equus caballus) liver EE isoenzyme (EqADH). MmADH alpha is stereoselective for the R isomer of 2-butanol, whereas EqADH favors the S isomer. Both enzymes have comparable reactivity with larger primary alcohols. MmADH alpha is more reactive with secondary alcohols and has highest activity with cyclohexanol. However, it does not react with steroids such as 5 beta-androstane-17 beta-ol-3-one. Molecular modeling suggests that the differences between MmADH alpha and EqADH are a result of the substitution of Ala for Phe93 and Thr for Ser48. MmADH alpha binds NAD+ most rapidly when a group with a pK of 7.4 is unprotonated, implicating His51 in this reaction. The G47R substitution decreased the dissociation constants for NAD+ and NADH and turnover numbers only about 2-fold, whereas the G47H substitution increased dissociation constants 7-14-fold and turnover numbers 4-fold. A basic residue at position 47 is not crucial for activity, as multiple interactions determine coenzyme affinity. 相似文献
96.
97.
Imadul Islam Shendong Yuan Christopher W. West Marc Adler Ulrich Bothe Judi Bryant Zheng Chang Kieu Chu Kumar Emayan Giovanna Gualtieri Elena Ho David Light Cornell Mallari John Morser Gary Phillips Caralee Schaefer Drew Sukovich Marc Whitlow Brad O. Buckman 《Bioorganic & medicinal chemistry letters》2018,28(20):3372-3375
We report here the design and synthesis of a novel series of benzylamines that are potent and selective inhibitors of uPA with promising oral availability in rat. Further evaluation of one representative (ZK824859) of the new structural class showed that this compound lowered clinical scores when dosed in either acute or chronic mouse EAE models, suggesting that uPA inhibitors of this type could be useful for the treatment of multiple sclerosis. 相似文献
98.
A large-subunit mitochondrial ribosomal DNA sequence translocated to the nuclear genome of two stone crabs (Menippe) 总被引:1,自引:0,他引:1
Two DNA sequences that appear to be homologous to large-subunit
mitochondrial ribosomal RNA genes have been identified in the stone crabs
Menippe mercenaria and M. adina. Amplification from whole genomic DNA by
polymerase chain reaction (PCR) with oligonucleotide primers based on
conserved portions of large-subunit mitochondrial rRNA genes consistently
amplified two products of similar length (565 and 567 bp). These products
differed at 3% of their nucleotide bases, and could be distinguished by a
HindIII site. Only one of these sequences (designated the A sequence) was
detected by PCR in purified mitochondrial DNA. The other (designated the B
sequence) hybridized to total genomic DNA at a level consistent with a
nuclear genome location. It is unlikely that the type B product would have
been recognized as a nuclear copy by examination of its sequence alone.
This is the first report of a mitochondrial gene sequence translocated into
the nuclear genome of a crustacean.
相似文献
99.
100.