BALB/c males were mated with Swiss Webster/HPB females to produce a first generation cross. Hybridoma cells derived from fusing SP2/0 myeloma cells and histocompatible spleen cells were injected intraperitoneally into...
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BALB/c males were mated with Swiss Webster/HPB females to produce a first generation cross. Hybridoma cells derived from fusing SP2/0 myeloma cells and histocompatible spleen cells were injected intraperitoneally into these mice to induce formation of ascites tumors and production of ascitic fluid containing large quantities of monoclonal antibody. Mice, 80 days old weighing between 28 g to 35 g, were treated with 0.5 ml of pristane 18 days before inoculation of 3.2 .times. 106 hybridoma cells. The first generation crosses, (BALB/c .male. .times. SW/HPB .female.)f1, produced up to 4 times more ascitic fluid of equally high antibody level over a longer period compared to the BALB/c parent. This first generation cross is a cost effective means for monoclonal antibody production.
作者：
HARPER, JfUNIV TEXAS
SCH MED DEPT PHARMACOL HOUSTON TX 77225 USA UNIV TEXAS
SCH MED DEPT INTERNAL MED HOUSTON TX 77225 USA
A computer program to calculate precise solutions (exact to the limit of computer accuracy) for the cumulative distribution function of the statistical t and f distributions is detailed. A routine that makes iterative...
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A computer program to calculate precise solutions (exact to the limit of computer accuracy) for the cumulative distribution function of the statistical t and f distributions is detailed. A routine that makes iterative calls of this algorithm to calculate precisely the inverse function of these distributions by successive approximation is also provided. The program provided yields precise levels of probability confidence of both fisher''s f and Student''s t tests, and the inverse calculation of critical values given p. It is written in a subset of BASIC which should run on any small computer, requiring only 1538 bytes on the Commodore 64.
The orientation of specific polypeptides of the cytochrome b6-f complex with respect to the chloroplast stromal phase was studied using trinitrobenzenesulfonate (TNBS) and pronase E as impermeant modifying reagents. O...
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The orientation of specific polypeptides of the cytochrome b6-f complex with respect to the chloroplast stromal phase was studied using trinitrobenzenesulfonate (TNBS) and pronase E as impermeant modifying reagents. Of the 4 polypeptides of the complex (33, 23, 20 and 17 kilodaltons) only cytochrome f was labeled by 14C-TNBS in unfractionated membranes. However, to a varying degree, all of the constitutent polypeptides were sensitive to pronase digestion and, in the case of cytochrome f, it was possible by immunoblotting techniques to idenify several degradation products. These results are discussed in relation to the organization of the cytochrome complex in thylakoid membranes and argue for an exposure to the stromal phase of all of the polypeptides, while functional considerations indicate that at least cytochrome f and the Rieske fe-S protein have a possible transmembrane organization.
The conditions for reconstitution of Cf0f1 [proton-translocating ATPase from chloroplasts] into asolectin liposomes and for ATP synthesis driven by an artifically generated .DELTA.~.mu.H+ [transmembrane electrochemica...
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The conditions for reconstitution of Cf0f1 [proton-translocating ATPase from chloroplasts] into asolectin liposomes and for ATP synthesis driven by an artifically generated .DELTA.~.mu.H+ [transmembrane electrochemical potential difference of protons] were optimized. A rate of maximally 200 ATP per Cf0f1 s-1 was obtained with a multi-mixing quenched-flow technique. This rate is about half the maximal rate observed in natural thylakoid membranes.
An antibody was raised to cross-linked ox-heart mitochondrial inhibitor protein, which cross-reacted with the free inhibitor but with no other mitochondrial membrane protein. This antibody yielded an immunoprecipitate...
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An antibody was raised to cross-linked ox-heart mitochondrial inhibitor protein, which cross-reacted with the free inhibitor but with no other mitochondrial membrane protein. This antibody yielded an immunoprecipitate with the cross-linked inhibitor protein, but a soluble antibody-antigen complex with free inhibitor. The antibody bound well to inhibitor protein whether the latter was complexed with f1-ATPase or not. Antibody binding had no effect on the ability of the inhibitor protein to inhibit the ATPase activity off1. These findings suggest that the antibody does not block the site of interaction between the inhibitor and f1. The inhibitor protein content of submitochondrial membrane preparations was determined by radioimmunoassay, activity measurements and an immunochemical back titration technique. The inhibitor content of submitochondrial membrane preparations was determined by radioimmunoassay, activity measurements and an immunochemical back titration technique. The inhibitor content of the membranes was shown to decrease after energization, suggesting a loss of inhibitor from the membranes into solution. Binding antibody to the inhibitor protein on submitochondrial membrane preparations was determined by radioimmunoassay, activity measurements and an immunochemical back titration technique. The inhibitor content of the membranes was shown to decrease after energization, suggesting a loss of inhibitor for the membranes into solution. Binding antibody to the inhibitor protein on submitochondrial particles had no effect on the steady-state rate of phosphorylation, but it increased the lag phase preceding phosphorylation from 30-54 s. The rate constant for the approach to the steady state dropped from 0.078-0.052 s-1. This effect confirmed that the lag phase is due to inhibition of phosphorylation by the inhibitor protein. The increase in ATPase activity following energization takes place by a fast phase (80% maximal activity reached within 90 s) and a slower
Numbers of the Photosystem I reaction center complexes and the cytochrome b6-f complexes with which a cytochrome c-553 molecule can interact within the limiting time of photosynthetic electron transport were examined ...
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Numbers of the Photosystem I reaction center complexes and the cytochrome b6-f complexes with which a cytochrome c-553 molecule can interact within the limiting time of photosynthetic electron transport were examined by measuring flash-induced absorption changes of P-700, cytochrome c-553 and cytochrome f in the thermophilic cyanobacterium Synechococcus sp. The addition of 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB) did not affect the common 2 ms half-time of P-700, cytochrome c-553 and cytochrome f reduction, which is ascribed to electron transfer from the plastoquinone pool. The inhibitor decreased amounts of the 3 electron carriers which underwent the 2 ms reduction in the order of cytochrome f, cytochrome c-553 and P-700.. On excitation with weak flashes which oxidized only a small fraction of cytochrome c-553 molecules present in cells, P-700 remained in the oxidized state after the flashes were reduced with electrons from the Rieske center or plastoquinone but not from cytochrome c-553. The ratios of cytochrome c-553 to cytochrome f oxidized at various flash intensities were constant and similar to the ratio of the 2 cytochromes present in cells. Thus, cytochrome c-553 cannot exchange electrons with large numbers of the Photosystem I reaction center complexes and the cytochrome b6-f complexes in the limiting time, but has a mobility sufficient to mediate electron transfer between the 2 complexes, which are present at an unbalanced ratio in Synechococcus cells.
A photosynthetic mutant of Lemna perpusilla (no. 1073) has been examined by spectrophotometric and immunoblotting techniques in order to localize the site of defect. In contrast to previous conclusions (Shahak, Y., Po...
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A photosynthetic mutant of Lemna perpusilla (no. 1073) has been examined by spectrophotometric and immunoblotting techniques in order to localize the site of defect. In contrast to previous conclusions (Shahak, Y., Posner, H.B. and Avron, M. (1976) Plant Physiol. 57, 577-679), neither cytochrome f nor cytochrome b6 could be detected spectrophotemetrically in the mutant. furthermore, immunoblotting using antibodies specific for each of the four constituent subunits of the cytochrome b6-f complex demonstrate that the entire complex is absent in the mutant. The light-harvesting chlorophyll-protein complex of Photosystem II is present in similar amounts in wild-type and mutant Lemna. However, the total amount of plastoquinone-9 is reduced by approx. 65% in the mutant strain, while the photoreducible plastoquinone-9 pool is comparable in wild-type and mutant Lemna.
The kinetic behaviour of the ATPase activity of beef heart f1 depends largely on the exposure of the enzyme to some anionic ligands such as sulphate and/or EDTA. f1 prepared in the presence of such anions exhibited a ...
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The kinetic behaviour of the ATPase activity of beef heart f1 depends largely on the exposure of the enzyme to some anionic ligands such as sulphate and/or EDTA. f1 prepared in the presence of such anions exhibited a triphasic kinetic pattern whereas f1 from which those anions were removed by dialysis exhibited only two Km values for ATP. Conversely to what has been previously reported, bicarbonate did not linearize f1-ATPase kinetics. Moreover, anion activation cannot be simply explained by promotion of ADP release but mainly by an increase in affinity of the third catalytic site for ATP.
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