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121.
122.
Helmut Ponta Karl-Heinz Altendorf Manfred Schweiger Monica Hirsch-Kaufmann Mei-Li Pfennig-Yeh Peter Herrlich 《Molecular & general genetics : MGG》1976,149(2):145-150
Summary Infection of E. coli with the viruses T7 or T3 leads to a dramatic efflux of potassium ions. This ion efflux is caused by the virus particle since no concomitant protein synthesis is required. T7 mutants carrying deletions in the M-gene (Schweiger et al., 1975), however, yield virus particles disturbed in the ion release. 相似文献
123.
Photosynthetischer Elektronentransport der Alge Bumilleriopsis während der Zellentwicklung 总被引:1,自引:1,他引:0
Summary The alga Bumilleriopsis filiformis Vischer (Xanthophyceae) was synchronized by light intensity combined with temperature changes. During the 48-h cell cycle there is a stage of low cellular photosynthetic activity in the 34th hour after start of the cycle and one of high activity between the 39th and 41th hour. These activities were compared with the p-benzoquinone mediated Hill reaction of non-homogenized cells and electron transport rates measured with carefully isolated chloroplast material. Ferricyanide and methylviologen reduction was tested with water as donor and photosystem I reactions with reduced dichloro-phenolindophenol and diaminodurene. The influence of superoxide dismutase and ascorbate was examined. The data show parallel changes in the activities of electron transport and cellular photosynthesis during cell development and indicate corresponding alteration not only in the activity of photosystem II but also in that of system I.
Abkürzungen pBQ p-Benzochinon - Chl Chlorophyll - DAD 2,3,5,6-Tetramethyl-p-phenylendiamin (Diaminodurol) - DCMU 3-(3,4-Dichlorphenyl)-1,1-dimethylharnstoff - DCIP 2,6-Dichlorphenolindophenol - FCCP Carbonylcyanid-p-trifluormethoxyphenyl-hydrazon - FeCy Kaliumhexacyano-(III)-ferrat - LST (Stark)-Licht-Schwachlicht-Temperaturwechsel (zur Synchronisierung) - MV Methylviologen (1,1-Dimethyl-4,4-dipyridylium-dichlorid) - PS-I, PS-II Photosystem I bzw, II - SOD Superoxid-Dismutase - TRICIN N-Tris-(hydroxymethyl)-methylglycin (Puffer) 相似文献
Abkürzungen pBQ p-Benzochinon - Chl Chlorophyll - DAD 2,3,5,6-Tetramethyl-p-phenylendiamin (Diaminodurol) - DCMU 3-(3,4-Dichlorphenyl)-1,1-dimethylharnstoff - DCIP 2,6-Dichlorphenolindophenol - FCCP Carbonylcyanid-p-trifluormethoxyphenyl-hydrazon - FeCy Kaliumhexacyano-(III)-ferrat - LST (Stark)-Licht-Schwachlicht-Temperaturwechsel (zur Synchronisierung) - MV Methylviologen (1,1-Dimethyl-4,4-dipyridylium-dichlorid) - PS-I, PS-II Photosystem I bzw, II - SOD Superoxid-Dismutase - TRICIN N-Tris-(hydroxymethyl)-methylglycin (Puffer) 相似文献
124.
Growing lily (Lilium longiflorum Thunb.) pollen always drive a current into their tubes and out of their grains. The only external ions needed for growth (and the growth current) are K+, H+, and Ca2+. Increases in K+ immediately stimulate the current; while decreases in K+ immediately inhibit it. Comparable changes in H+ have the opposite effect; while those in Ca2+ have very little effect. We infer that most of the steady growth current is carried in by a potassium leak and out by a proton pump; but other considerations indicate that a minor, but controlling, component of the inward current consists of calcium ions. 相似文献
125.
Manfred Grieshaber Gerd Gäde 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1976,108(3):225-232
Summary The enzymatic activities of glyceraldehyde-3-phosphate dehydrogenase, octopine dehydrogenase and lactate dehydrogenase were determined fromLoligo vulgaris. Octopine dehydrogenase displays the highest activity yet recorded for this enzyme, exceeding glyceraldehyde-3-phosphate dehydrogenase sixfold and lactate dehydrogenase 365-fold (Table 1).During jet propulsion swimming octopine accumulates instead of lactate (Table 2), while phosphoarginine, the phosphagen of the squid, is depleted (Table 3).The formation of octopine is discussed in relation to anaerobic metabolism which might occur during burst activity in cephalopods.The following abbreviations are used
AK
arginine kinase (2.7.3.3)
-
GAPDH
glyceraldehyde-3-phosphate dehydrogenase (1.2.1.12)
-
LDH
L-lactate
-
NAD
oxidoreductase (1.1.1.27)
-
ODH
octopine
-
NAD
oxidoreductase (1.5.1.11)
-
DTT
dithiothreitol
-
dw
dry weight (about 20% of the fresh weight)
This investigation was generously supported by The Deutsche Forschungsgemeinschaft grant No.: (Ze 40/13) 相似文献
126.
Janice L. White Marvin L. Hackert Manfred Buehner Margaret J. Adams Geoffrey C. Ford Paul J. Lentz Ira E. Smiley Steven J. Steindel Michael G. Rossmann 《Journal of molecular biology》1976,102(4):759-779
Details are recorded of the X-ray diffraction data collection, heavy atom refinement and preliminary structure refinement for two different dogfish M4 lactate dehydrogenase structures. One of these is the 2.0 Å resolution apoenzyme structure; the other is a 3.0 Å resolution abortive ternary complex. Two other ternary substrate inhibitory complexes (LDHase2: NAD: oxalate and LDHase: NADH: oxamate), isomorphous with the abortive ternary complex (LDHase: NAD-pyruvate), have also been examined. The apo-LDHase and LDHase: NAD-pyruvate structures are systematically compared to determine significant differences in their conformation. These are related to differences in structure amongst the three studied ternary complexes. These differences all occur in regions of the protein around the active site, particularly the flexible loop covering the active center pocket and the C-terminal helix αH. The changes are suggestive of a domino effect whereby the closing of the loop on binding coenzyme and substrate triggers the critical reactive residues into assuming their catalytically active positions. 相似文献
127.
Summary A deficient G-6PD variant was discovered in 4 males of one family from north-western Germany. Five generations of this family could be studied.The deficient G-6PD was a new variant, called Gd (-) Aachen. Its main characteristics are the following: severe enzyme deficiency in erythrocytes (3% of normal), contrasting with an almost normal activity in leukocytes; normal molecular specific activity (i.e., normal ratio enzyme activity/cross-reacting material); slow mobility in starch gel electrophoresis (92–94% of normal); increased Michaelis constant for glucose-6-phosphate (60–70 M) and NADP+ (20–25 M); decreased inhibition constant by NADPH with respect to NADP+ (7 M); increased inhibition by ATP; normal utilization of the substrate analogues; slightly biphasic pH curve; thermal instability, and normal activation energy of the enzymatic reaction.The relationships between the hematologic disorders (severe and frequent hemolytic crises) and the unfavorable kinetic modifications are discussed.with the technical assistance of Joelle Marie and Dominique CottreauDedicated to Prof. Dr. H. Schonenberg, Aachen, on his 60th birthday. The first results of this work were presented in part at the Kongress der Deutschen Kinderärzte, München. 相似文献
128.
Peter Schneider Manfred Hermes 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1976,106(1):39-49
The function of the flapping elytra was investigated in garden shafers (Melolontha melolontha L.) and rhinoceros beetles (Oryctes boas Fabr.).
相似文献
1. | The movements of alae and elytra are determined. Both move with the same frequency and in the same phase, but the range of the elytral stroke never reaches below the frontal plane. In downstroke the elytra are at an angle positive to the airstream (horizontal flight). |
2. | After exact investigation of the construction of the elytra (depth, width, length, surface, torsion and velocity of each point of the elytra) the most effective point in the production of lift during the downstroke was determined. |
3. | After loss of one third of the surface of the elytra the beetles cannot fly horizontally. In tethered flight the wing stroke frequency of the alae does not increase when the elytra are shortened. Shortening of the elytra does not interfere with the resonance system of the pterothorax. |
4. | The lift of the elytra results from active and passive components (more than 17% of the body weight). In the airstream (front 2.00 m/s, average body weight 944 mp) the passive lift is 14.3% for elytra in the down position; 3.1% of the lift is caused by the active downstroke. |
5. | The elytra of these beetles are indispensible for horizontal flight. Primarily they produce lift passively with added help from the downstroke, and have no function for the drag. The effect of upstroke is discussed. |
129.
Veronica lycica
Lehm. is a distinct, diploid member of theVeronica cymbalaria group, endemic in Lycia (S.W. Anatolia). Closely related is the newV. stamatiadae
M. Fischer etW. Greuter which is also diploid and seems to be restricted to the small Greek island Ro close to the South coast of Lycia. The chromosome numbers for both species are reported for the first time (2n = 18).
Untersuchungen über den PolyploidkomplexVeronica cymbalaria agg., II. — Der erste Beitrag dieser Serie:Fischer (1975). 相似文献
130.
Prof. Dr. Manfred Gersch Heiner Birkenbeil Joachim Ude 《Cell and tissue research》1975,160(3):389-397
The prothoracic glands of the last instar of Galleria mellonella undergo characteristic alterations of their cellular fine structure closely related to cellular activity. During progressive secretory activity of the gland cells there are extensive plasmalemmal infoldings and formation of a pronounced lacunar system. Mitochondria of the active cell phase are characterized by a specific increase in size and paler colour of the matrix. In contrast to the alterations, nuclei, ER and Golgi cisterns do not undergo any submicroscopic changes during the different phases of cellular activity. The relationship between the substructural phenomena and the specific phases of cellular activity are discussed. 相似文献