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C A Buck

Publications and source records attributed to C A Buck.

90 records · Page 5Linked to original sources

Surface glycoproteins of normal and transformed cells: a difference determined by sialic acid and a growth-dependent sialyl transferase.

The pattern of elution from a column of Sephadex G-50 of a fucose-labeled carbohydrate component derived from the surface glycoproteins of transformed cells can be altered to resemble that from untransformed cells by enzymatic removal of the sialic acid. These results indicate that the consistent differences found between control and virus-transformed cells may depend upon a relatively specific sialyl transferase that is found in greater amounts (2.5- to 11-times) in transformed cells than in control cells, and in dividing cells as compared to nondividing cells.

Animals↗

Glycopeptides from the surface of control and virus-transformed cells.

Glycopeptides were removed by trypsin digestion from the surface of control cells and cells transformed by Rous sarcoma virus, murine sarcoma virus, or polyoma virus. After digestion with pronase, the glycopeptides were analyzed by gel filtration. The elution profiles suggest that there are differences in the glycopeptides from the surface of control cells and those from transformed cells.

Animals↗

System of double infection between vaccinia virus and mengovirus.

When L cells are simultaneously infected with vaccinia virus and mengovirus, double interference in the replication of both viruses is observed. Superinfection of vaccinia virus-infected cells by mengovirus during the first 5 hr of infection reduces vaccinia virus yields to between 1 and 3% of controls. The yields of mengovirus are reduced to between 1 and 16% of controls, depending upon the time of superinfection. The replication of vaccinia deoxyribonucleic acid is not inhibited by mengovirus; it is only delayed. On the other hand, vaccinia multiplication severely hinders the replication of mengovirus ribonucleic acid. The double-infected system, at early times, synthesizes proteins that resemble those synthesized in the vaccinia virus-infected cells. Later in infection, however, the pattern is switched to proteins synthesized by mengovirus-infected cells. Possible mechanisms for this double interference in multiplication are discussed.

Animals↗

Comparative hybridization of mitochondrial and cytoplasmic aminoacyl transfer RNA with mitochondrial DNA from rat liver.

We have tested the specificity of hybridization of mitochondrial tRNA with mitochondrial DNA. Techniques are now available for performing RNA-DNA hybridization at low temperatures in the presence of 50 per cent formamide. With this technique, specific aminoacyl-tRNA-DNA hybridization can be followed in the presence of other species of RNA if the tRNA is acylated with radioactive amino acids. With this technique, mitochondrial leucyl-tRNA from rat liver has been found to anneal to mitochondrial DNA. Competitive hybridization between mitochondrial leucyl-tRNA and mitochondrial or cytoplasmic aminoacyl-tRNA shows that mitochondrial tRNA competes much more efficiently than cytoplasmic tRNA for sites of annealing to mitochondrial DNA. These results show that mitochondrial leucyl-tRNA differs from cytoplasmic leucyl-tRNA in its primary base sequence. They also imply that mitochondrial DNA may be the template from which mitochondrial tRNA is transcribed.

Amino Acids↗