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J E Ladner

Publications and source records attributed to J E Ladner.

25 records · Page 2Linked to original sources
PubMed1974

Conservation of the molecular structure of yeast phenylalanine transfer RNA in two crystal forms.

A comparison is made between the electron density maps of the monoclinic and orthorhombic crystal forms of yeast tRNA(Phe) which have been obtained respectively by ourselves and by another group. It is concluded that the molecular structures are essentially the same in both crystals, although the models derived from the maps are not the same. The relation between the two molecular packings is discussed, and it is suggested that the intermolecular contact in the orthorhombic form which is not present in the monoclinic form, may arise through base pairing of the anticodons of neighboring molecules.

Models, Molecular↗
PubMed1974

Effects of dilute HCl on yeast tRNAPhe and E. coli tRNA1fMet.

HCl treatment of yeast tRNA(Phe) under conditions generally used for excision of ;Y' base results in structure and conformation changes as monitored by line widths in the PMR spectra at 220 MHz and by optical rotation. Like exposure of E. coli tRNA(fMet) (1) causes similar changes in the PMR spectra and optical rotation although no residues are eliminated. Electrophoresis in polyacrylamide gels provides evidence for aggregation in HCl-treated tRNA(fMet) (1). One must thus consider a general effect of HCl exposure as well as possible residue removal in assessing induced structural and conformation changes in tRNA.

Computers↗
PubMed1974

Correlation between three-dimensional structure and chemical reactivity of transfer RNA.

The bases of yeast tRNA(Phe) which react with carbodiimide and methoxyamine have been determined and this information has been combined with chemical modification studies of other workers to produce a composite picture of base accessibility in this tRNA. The results are compared with the three-dimensional structure which we have recently determined. The bases which react chemically lie in exposed positions in the three-dimensional model and those which do not are either in the double helical stem regions or else are involved in maintaining the tertiary structure through pairing or stacking interactions.

Base Sequence↗