In the Search for New Anticancer Drugs. 27. Synthesis and Comparison of Anticancer Activity in Vivo of Amino Acids, Carbohydrates, and Carbohydrate-Amino Acid Conjugates Containing the [N′‐(2‐chloroethyl)‐N′‐nitrosoamino]carbonyl group

1994 ◽  
Vol 83 (7) ◽  
pp. 989-998 ◽  
Author(s):  
George Sosnovsky ◽  
C. Thomas Gnewuch
1983 ◽  
Vol 38 (9) ◽  
pp. 1138-1141 ◽  
Author(s):  
Maria Konieczny ◽  
Peter L. Gutierrez ◽  
George Sosnovsky

Abstract In order to test the effect of selenium on the anticancer activity of alkylating drugs, Seleno-TEPA (4), the selenium analog of the clinically used Thio-TEPA (1) was tested in vivo against the lymphocytic P 388 and lymphoid L1210 murine leukemias. Compound 4 is more active against P 388 leukemia than against L1210, and appears to be active over a narrower concentration range than Thio-TEPA (1). Compound 4 is less active against P 388 leukemia than 1, as evidenced by the T/C values of 164 for 4 and 239 for 1 at a dose of 4.2 mg/kg. The activity of 4 was also evaluated on the HL60 and K 562 human cell lines. Under the conditions of the cell colony assay technique, Seleno-TEPA (4) is less effective than Thio-TEPA (1).


1987 ◽  
Vol 7 (1) ◽  
pp. 294-304 ◽  
Author(s):  
D Pilgrim ◽  
E T Young

Alcohol dehydrogenase isoenzyme III (ADH III) in Saccharomyces cerevisiae, the product of the ADH3 gene, is located in the mitochondrial matrix. The ADH III protein was synthesized as a larger precursor in vitro when the gene was transcribed with the SP6 promoter and translated with a reticulocyte lysate. A precursor of the same size was detected when radioactively pulse-labeled proteins were immunoprecipitated with anti-ADH antibody. This precursor was rapidly processed to the mature form in vivo with a half-time of less than 3 min. The processing was blocked if the mitochondria were uncoupled with carbonyl cyanide m-chlorophenylhydrazone. Mutant enzymes in which only the amino-terminal 14 or 16 amino acids of the presequence were retained were correctly targeted and imported into the matrix. A mutant enzyme that was missing the amino-terminal 17 amino acids of the presequence produced an active enzyme, but the majority of the enzyme activity remained in the cytoplasmic compartment on cellular fractionation. Random amino acid changes were produced in the wild-type presequence by bisulfite mutagenesis of the ADH3 gene. The resulting ADH III protein was targeted to the mitochondria and imported into the matrix in all of the mutants tested, as judged by enzyme activity. Mutants containing amino acid changes in the carboxyl-proximal half of the ADH3 presequence were imported and processed to the mature form at a slower rate than the wild type, as judged by pulse-chase studies in vivo. The unprocessed precursor appeared to be unstable in vivo. It was concluded that only a small portion of the presequence contains the necessary information for correct targeting and import. Furthermore, the information for correct proteolytic processing of the presequence appears to be distinct from the targeting information and may involve secondary structure information in the presequence.


1972 ◽  
Vol 54 (2) ◽  
pp. 279-294 ◽  
Author(s):  
David C. Shephard ◽  
Wendy B. Levin

The ability of chloroplasts isolated from Acetabulana mediterranea to synthesize the protein amino acids has been investigated. When this chloroplast isolate was presented with 14CO2 for periods of 6–8 hr, tracer was found in essentially all amino acid species of their hydrolyzed protein Phenylalanine labeling was not detected, probably due to technical problems, and hydroxyproline labeling was not tested for The incorporation of 14CO2 into the amino acids is driven by light and, as indicated by the amount of radioactivity lost during ninhydrin decarboxylation on the chromatograms, the amino acids appear to be uniformly labeled. The amino acid labeling pattern of the isolate is similar to that found in plastids labeled with 14CO2 in vivo. The chloroplast isolate did not utilize detectable amounts of externally supplied amino acids in light or, with added adenosine triphosphate (ATP), in darkness. It is concluded that these chloroplasts are a tight cytoplasmic compartment that is independent in supplying the amino acids used for its own protein synthesis. These results are discussed in terms of the role of contaminants in the observed synthesis, the "normalcy" of Acetabularia chloroplasts, the synthetic pathways for amino acids in plastids, and the implications of these observations for cell compartmentation and chloroplast autonomy.


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