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The influence of wilting on the levels of free proline, soluble proteins, reducing sugars, starch and on the activities of
nitrate reductase, invertase, amylase and pyrophosphatases have been studied in the leaf tissue of five cultivars of pearl
millet at their vegetative stage under pot culture conditions. The metabolic changes could not be correlated with the yield
behaviour of the cultivars under a drought condition in the field. 相似文献
3.
J Leikola H H Fudenberg G N Vyas H A Perkins 《Journal of immunology (Baltimore, Md. : 1950)》1971,106(5):1147-1153
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N-Methyl-4-nitroaniline (MNA) is used as an additive to lower the melting temperature of energetic materials in the synthesis of insensitive explosives. Although the biotransformation of MNA under anaerobic condition has been reported, its aerobic microbial degradation has not been documented yet. A soil microcosms study showed the efficient aerobic degradation of MNA by the inhabitant soil microorganisms. An aerobic bacterium, Pseudomonas sp. strain FK357, able to utilize MNA as the sole carbon, nitrogen, and energy source, was isolated from soil microcosms. HPLC and GC-MS analysis of the samples obtained from growth and resting cell studies showed the formation of 4-nitroaniline (4-NA), 4-aminophenol (4-AP), and 1, 2, 4-benzenetriol (BT) as major metabolic intermediates in the MNA degradation pathway. Enzymatic assay carried out on cell-free lysates of MNA grown cells confirmed N-demethylation reaction is the first step of MNA degradation with the formation of 4-NA and formaldehyde products. Flavin-dependent transformation of 4-NA to 4-AP in cell extracts demonstrated that the second step of MNA degradation is a monooxygenation. Furthermore, conversion of 4-AP to BT by MNA grown cells indicates the involvement of oxidative deamination (release of NH2 substituent) reaction in third step of MNA degradation. Subsequent degradation of BT occurs by the action of benzenetriol 1, 2-dioxygenase as reported for the degradation of 4-nitrophenol. This is the first report on aerobic degradation of MNA by a single bacterium along with elucidation of metabolic pathway. 相似文献
7.
The inertness of the alkenic bond towards electrophilic additions in 3-exocyano-3-(methylthio)-2-thiabicyclo[2.2.1]hept-5-ene S,S,S′,S′-tetraoxide (5), 3,6-dihydro-2-(methylthio)-2H-thiopyran-2-carbonitrile S,S,S′,S′-tetraoxide (3), and 2-(acetamidomethyl)-3,6-dihydro-2-(methylthio)-2H-thiopyran S,S,S′,S′-tetraoxide (4) is attributed to the “supra-annular effect” and field effects. Conformational analysis of a pentadeuterated derivative of 4 (10) is reported. On the basis of the 220-MHz 1H n.m.r.-spectral data of 10, the compound was concluded to adopt the 0H2 conformation in chloroform solution. 相似文献
8.
The present contribution incorporates an account of the distribution of adenosine triphosphatase and its functional role in various regions of the alimentary canal of Pheretima posthuma and Barogaster annandalei. The main areas, showing adenosine triphosphatase activity in P. posthuma are sub-epithelial blood vessels in pharynx, peri-oesophageal blood vessels in oesophagus, columnar epithelial cells of gizzard and in the areas outside the typhlosole and around the supra-intestinal excretory ducts. In B. annandalei the epithelial cells of gizzard show significant enzymatic localization. In addition to this, enzymatic activity has also been found in the deeply embedded blood vessels of buccal region, peri-oesophageal vasculature, sub-epithelial vasculature of typhlosole and intestine, and in the adjoining chloragogen cells. Physiological significance of the enzymatic pattern has been discussed. 相似文献
9.
A new rapid method for genetic typing of human immunoglobulins 总被引:22,自引:0,他引:22
G N Vyas H H Fudenberg H M Pretty E R Gold 《Journal of immunology (Baltimore, Md. : 1950)》1968,100(2):274-279
10.
Effect of controlled carbon dioxide on in vitro shoot multiplication in Feronia limonia (L.) Swingle
The effect of controlled carbon dioxide environment on in vitro shoot growth and multiplication in Feronia limonia (a tropical fruit plant, Family- Rutaceae) was studied. Carbon dioxide available in the ambient air of the growth room was
insufficient for in vitro growth of the shoots alone. Also, the presence of sucrose only as the C-source in the medium (without CO2), was found to be inadequate for sustainable growth and multiplication of shoots. The carbon dioxide enrichment promoted
shoot multiplication and overall growth. The promotory effect of CO2 was independent of the presence of sucrose in the medium. In the presence of both CO2 and sucrose, an additive effect was observed producing maximum shoot growth. In the absence of sucrose a higher concentration
of CO2 (10.0)g m−3 was required to achieve photoautotrophic shoot multiplication comparable to ambient air controls. Highest leaf area per shoot
cluster promoting shoot growth and multiplication was recorded under this treatment. Shoots growing on sucrose containing
medium under controlled CO2 environment of 0.6 g m−3 concentration evoked better response than ambient air controls (shoots growing on sucrose containing medium) in growth room.
This treatment produced the overall best response. The present study highlighted the possibility of photoautotrophic multiplication
which might prove useful for successful hardening and acclimatization in tissue culture plants. 相似文献