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Biomedical subjects

R Zúñiga

Publications and source records attributed to R Zúñiga.

4 recordsLinked to original sources

A dual-specific Glu-tRNA(Gln) and Asp-tRNA(Asn) amidotransferase is involved in decoding glutamine and asparagine codons in Acidithiobacillus ferrooxidans.

The gatC, gatA and gatB genes encoding the three subunits of glutamyl-tRNA(Gln) amidotransferase from Acidithiobacillus ferrooxidans, an acidophilic bacterium used in bioleaching of minerals, have been cloned and expressed in Escherichia coli. As in Bacillus subtilis the three gat genes are organized in an operon-like structure in A. ferrooxidans. The heterologously overexpressed enzyme converts Glu-tRNA(Gln) to Gln-tRNA(Gln) and Asp-tRNA(Asn) to Asn-tRNA(Asn). Biochemical analysis revealed that neither glutaminyl-tRNA synthetase nor asparaginyl-tRNA synthetase is present in A. ferrooxidans, but that glutamyl-tRNA synthetase and aspartyl-tRNA synthetase enzymes are present in the organism. These data suggest that the transamidation pathway is responsible for the formation of Gln-tRNA and Asn-tRNA in A. ferrooxidans.

Asparagine↗

Partial trisomy-5p.

Two sibs with partial trisomy-5p are reported. Their father is the carrier of a balanced translocation 46,XY,t(4q+;5p-). Twelve cases of partial trisomy-5p--including our two patients--have been reported. The most common abnormalities found were mental retardation, short stature, dolichocephaly, prominent nasal bridge, prognathism, seizures, hypotonia, ear abnormalities, increased ulnar loops on the fingertips, and cryptorchidism in affected males.

Abnormalities, Multiple↗

"De novo" trisomy 1q32 leads to 1qter and monosomy 3p25 leads to 3pter.

Minor abnormalities are described in an 11-month-old female in which a "de novo" trisomy 1q32 leads to lqter and a monosomy 3p25 leads to ter has been produced. The amount of the exceeding material in this case is less than that found in previous reports of partial trisomy 1q and in cases of parental 1q balanced translocations which has originated recurrent abortions.

Aneuploidy↗