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Biomedical subjects

B J Ortwerth

Publications and source records attributed to B J Ortwerth.

At least 91 records · Page 5Linked to original sources
PubMed1979

Transfer RNATyr of melanoma tissues and cells: relevance to melanin synthesis?

The tRNA present in swine melanoma tumor tissue and normal gray skin tissue were compared by aminoacylation of the unfractionated tRNA preparations. Of the seventeen amino acids studied, seven showed differences in rate of acceptance to tRNAs from normal and tumor tissues; the tRNAs of two amino acids, tyrosine and glycine, showed dramatic three fold increases in melanoma tumor. As melanin biosynthesis proceeds from tyrosine oxidation the investigations focused on the increase in tyrosine tRNA. Kinetic analysis of tyrosine aminoacylation to normal and melanoma tRNAs revealed no differences. Analysis of the isoaccepting species of tRNATyr from normal skin and melanoma tumor tissues identified three isoacceptors; tRNATyr, represented the predominant species in normal gray skin, while tRNA2Tyr predominated in melanoma tumor tissue. The tyrosine acceptances by tRNAs from three human melanoma cell lines were analyzed and found to be variable, but isoaccepting species analysis of the tRNATyr of these three cell lines still showed a correlation between the preponderance of tRNA2Tyr and extent of tyrosine acceptance. Additionally the enzymatic activity for the oxidation of tyrosine was found to be related to tyrosine acceptance and tRNA2Tyr predominance..

Amino Acyl-tRNA Synthetases↗
PubMed1976

Lysine tRNA's associated with avian myeloblastosis virus 70S RNA.

The lysine tRNA released from the 70S RNA of avian myeloblastosis virus was separated by reversed-phase chromatography. All of the AAG-coding lysine tRNA's were present in the 70S-associated fraction; however, the AAA-coding lysine tRNA could not be detected. Chromatography of the lysine tRNA released at various temperatures did not show any preferential release of one AAG-coding species over another.

Avian Leukosis Virus↗