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Biomedical subjects

W W Ralph

Publications and source records attributed to W W Ralph.

3 recordsLinked to original sources

A modified Chou and Fasman protein structure algorithm.

A FORTRAN program PRSTRC has been developed for protein secondary structure prediction, which is a modified Chou and Fasman (1978) analysis. This implementation carries out a running average of amino acid structure occurrence frequencies, utilizes a simple set of nucleation conditions, and allows user control over nucleation threshold and cutoff parameters. The algorithm includes prediction of the newly defined secondary structure elements: omega loops (1986). It also generates a charge distribution and hydropathy profile. Output includes a simple graphic display for a printer, or a CRT using color addition. Correct structures are predicted for T. dyscritum hemerythrin and the variable domain of mouse immunoglobin k-chain.

Algorithms

Codon usage in the vertebrate hemoglobins and its implications.

A study of codon usage in vertebrate hemoglobins revealed an evolutionary trend toward elevated numbers of CpG codon boundary pairs in mammalian hemoglobin alpha genes. Selection for CpG codon boundaries countering the generally observed CpG suppression is strongly suggested by these data. These observations parallel recently published experimental results that indicate that constitutive expression of the human alpha-globin gene appears to be determined by regulatory information encoded within the structural gene. The possibility is raised that, in the absence of selection, CpG decay can be used to date the evolutionary origin of a mammalian alpha pseudogene from its active alpha gene.

Animals

Mapping the order of DNA restriction fragments.

A straightforward method was designed for mapping the order of DNA restriction fragments obtained by a double and two single digestions, without the necessity of using a computer or a radioactive label. All possible solutions compatible with a pre-set level of error in the determination of sequence lengths are obtained. The primary assumptions are given, and the appropriate modifications of the algorithm are presented as a function of any assumptions one is unable (or unwilling) to make. Use of the method in connection with end-labeled fragments is also described.

Chromosome Mapping