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911.
A tomato cDNA inducible by salt stress and abscisic acid: nucleotide sequence and expression pattern 总被引:2,自引:0,他引:2
We have characterized a new tomato cDNA, TAS14, inducible by salt stress and abscisic acid (ABA). Its nucleotide sequence predicts an open reading frame coding for a highly hydrophilic and glycine-rich (23.8%) protein of 130 amino acids. Southern blot analysis of tomato DNA suggests that there is one TAS14 structural gene per haploid genome. TAS14 mRNA accumulates in tomato seedlings upon treatment with NaCl, ABA or mannitol. It is also induced in roots, stems and leaves of hydroponically grown tomato plants treated with NaCl or ABA. TAS14 mRNA is not induced by other stress conditions such as cold and wounding. The sequence of the predicted TAS14 protein shows four structural domains similar to the rice RAB21, cotton LEA D11 and barley and maize dehydrin genes. 相似文献
912.
Lernanthropus huamani n. sp. (Copepoda: Lernanthropidae), a parasite of the Peruvian sciaenid fish Menticirrhus ophicephalus (Jenyns), is described and illustrated. The new species differs from all other species of Lernanthropus by a combination of characters, including the dorsal plate, legs and other appendages. L. guacoldae Villalba & Fernández, 1984 is considered a synonym of L. pacificus Oliva & Duran, 1982. 相似文献
913.
H. E. Witters S. Van Puymbroek I. Van Den Sande O. L. J. Vanderborght 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1990,160(5):563-571
Summary Elevated values of haematocrit were observed in rainbow trout (Oncorhynchus mykiss) during combined acid and aluminium exposure. Possible causes of this, i.e., decreased plasma volume, swelling of erythrocytes, and/or mobilization of erythrocytes into the blood were investigated. Slight haematocrit increases (10–20%) during mild acid stress (pH 5.0, 25 mol Ca2+·1-1) were mostly caused by osmotic shifts. Both swelling of erythrocytes rocytes and a significant decrease of the plasma volume were demonstrated in fish at pH 5.0. These osmotic disturbined were greater during acid exposure (pH 5.0) combined with Al (60 g·1-1; 200 g·1-1). In addition, numbers of erythrocytes increased by 40% compared to acid exposure, which contributed to the severe haematocrit rise (35%) during Al exposure. A contraction of the spleen releasing erythrocytes into the blood is suggested to occur as an adrenergic response to hypoxia, which is observed in fish acutely exposed to Al.Abbreviations
BV
blood volume
-
ECFV
extracellular fluid volume
-
ICFV
intracellular fluid volume
-
ISFV
interstitial fluid volume
-
MCHC
mean cell haemoglobin concentration
-
MCV
mean cell volume
-
PV
plasma volume 相似文献
914.
Adrie Ykema Elizabeth C. Verbree Ira I. G. S. Verwoert Karin H. van der Linden H. John J. Nijkamp Henk Smit 《Applied microbiology and biotechnology》1990,33(2):176-182
Summary From six unsaturated fatty acid auxotrophs (Ufa mutants) of the oleaginous yeast Apiotrichum curvatum blocked in the conversion of stearic to oleic acid, were isolated revertants able to grow in the absence of unsaturated fatty acids, in a search for strains that can produce cocoa butter equivalents. A broad range in the percentage of saturated fatty acids (%SFA) was observed in the lipids of individual revertants (varying from 27%–86% SFA), compared with the wild-type (44% SFA). Further analysis of fatty acid composition indicated that: (i) not all six Ufa mutants had the same genetic background and (ii) one specific Ufa mutation could be reverted in more than one way. Revertants that produced lipids with a %SFA>56%, were examined further. These strains were cultivated for 50 generations and half of them produced lipids with high %SFA after that time and were defined as stable. The viability of revertant strains with extremely high %SFA (>80%) may be explained by our finding that polar lipids, which are part of yeast membranes, contained much more polyunsaturated fatty acids and a significantly lower %SFA than neutral (storage) lipids. One revertant (R25.75) was selected that was able to produce lipids in whey permeate at a rate comparable with wild-type A. curvatum and with a fatty acid composition and congelation curve comparable with cocoa butter.
Offprint requests to: A. Ykema 相似文献
915.
M. I. Van Dyke W. Parker H. Lee J. T. Trevors 《Applied microbiology and biotechnology》1990,33(6):716-720
Summary The influence of pH, temperature and catechol concentration on germanium (Ge) accumulation byPseudomonas stutzeri AG259 was investigated. Increasing the incubation temperature or pH of the culture medium markedly enhanced Ge accumulation. High amounts of Ge were accumulated at pH 11 and at 50°C, conditions under whichP. stutzeri cells were non-viable. Ge accumulation was unaffected by treatment with toluene or 2,4-dinitrophenol. These results indicate that Ge was accumulated by an energy-independent process. Ge accumulation increased as the catechol concentration increased. The use of autoclaved catechol solutions consistently increased the amount of Ge accumulated at all concentrations of catechol tested. It is possible that Ge enters the bacterial cells as a Ge-catechol complex and this uptake is enhanced by autoclaved catechol. 相似文献
916.
W Musters K Boon C A van der Sande H van Heerikhuizen R J Planta 《The EMBO journal》1990,9(12):3989-3996
917.
The three-dimensional structure of the seed storage protein phaseolin at 3 A resolution. 总被引:4,自引:0,他引:4 下载免费PDF全文
M C Lawrence E Suzuki J N Varghese P C Davis A Van Donkelaar P A Tulloch P M Colman 《The EMBO journal》1990,9(1):9-15
The polypeptides of the trimeric seed storage protein phaseolin comprise two structurally similar units each made up of a beta-barrel and an alpha-helical domain. The beta-barrel has the 'jelly-roll' folding topology of the viral coat proteins and the alpha-helical domain shows structural similarity to the helix-turn-helix motif found in certain DNA-binding proteins. 相似文献
918.
Anterior basal encephalocele in the median cleft face syndrome. Comments on nosology and treatment 总被引:1,自引:0,他引:1
C Grubben J P Fryns F De Zegher H Van Den Berghe 《Genetic counseling (Geneva, Switzerland)》1990,1(2):103-109
Two cases of median cleft syndrome with associated basal encephalocele are presented. The median cleft face syndrome consists of several craniofacial defects and occurs, as far as we know, sporadically. Extracranial defects should be looked for carefully since they may indicate the presence of a specific syndrome with its own prognosis and mode of inheritance. Basal encephaloceles are sometimes part of the syndrome and may cause serious, or even life-threatening, symptoms. With regard to the treatment of basal encephaloceles there still exists a lot of controversion, but most authors agree that it is better to postpone operation until after the age of three because mortality is lower then. 相似文献
919.
This paper discusses the properties of bacterial haem-containing and non-haem haloperoxidases, their involvement in the biosynthesis of halometabolites and their use in bioconversion. The very low peroxidase activity of bacterial non-haem haloperoxidases, their stability at high temperature and over a wide pH-range makes them particularly suited for use in the bromination of organic compounds. The chloroperoxidase from Pseudomonas pyrrocinia is the only haloperoxidase showing substrate specificity and regioselectivity. The genes of one chloro- and one bromoperoxidase could be cloned. The corresponding enzymes can now be produced in large amounts and at low costs. 相似文献
920.
E J Wiertz H C Walvoort H Van Loveren I Van Straaten-Van De Kappelle J W Van Der Gun J G Kreeftenberg 《Biologicals》1990,18(3):173-180
Athymic (nu/nu) and euthymic (+/nu) BALB/c mice were immunized with a whole cell pertussis vaccine or with an acellular vaccine which contained detoxified pertussis toxin (PT) and filamentous hemagglutinin (FHA). Only the euthymic mice were protected against intracerebral challenge with virulent Bordetella pertussis which implies involvement of T-cells. As a cell transfer from mice immunized with whole cell or acellular vaccine prior to the challenge did not protect naive euthymic recipients, cellular immunity seems to be non-protective as an effector mechanism. Mice could be protected passively against a challenge by administration of immune sera. Therefore, T-cell dependent humoral immune responses to B. pertussis appear to be crucial for protection. The humoral response was further studied with athymic and euthymic mice. In euthymic mice the whole cell vaccine induced antibodies to FHA, pililipopolysaccharides (LPS) and an outer membrane protein (OMP) preparation, whereas the acellular vaccine induced antibodies to PT, FHA and OMP. Both IgM and IgG could be detected. From the nude mice only those immunized with the whole cell vaccine showed an antibody response which consisted of low titres of IgM directed to LPS. Sera from both +/nu and nu/nu mice immunized with the whole cell vaccine were bactericidal in vitro. These data demonstrate that in the mouse model protection to intracerebral challenge with B. pertussis is T-cell dependent as is the humoral response to PT, FHA, OMP and pili. The T-independent B-cell activation by the whole cell preparation is due to the presence of LPS.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献