Search PubMed⌕ Search

Biomedical subjects

S R Jordan

Publications and source records attributed to S R Jordan.

21 records · Page 2Linked to original sources
PubMed1983

Systematic analysis of possible hydrogen bonds between amino acid side chains and B-form DNA.

The ways in which amino acid side chains could make a pair of hydrogen bonds within the major groove of B DNA are systematically analyzed. Hydrogen bond donors within the major groove are characterized by determining the idealized position of the hydrogen bond acceptors that they might bond with. It appears that an amino acid side chain could, at most, contact a pair of base pairs. The ten possible pairs of base pairs are analyzed to determine how they could be recognized by the amino acid side chains.

Amino Acids↗
PubMed1977

Structural convergence during protein evolution.

Several recent protein crystallographic structure determinations have demonstrated the existence of considerable tertiary structural similarity among proteins otherwise having little similarity in either amino acid sequence or biological function. In order to assess the possibility that such proteins may have arisen through processes of divergent evolution from a common ancestor, a graphical presentation is given which correlates the pattern of allowed single base substitutions defined by the genetic code with the associated changes in the structural properties of the encoded amino acids. The results show that while a large degree of structural conservation is evident due to codon synonomy, there is, in general, little tendency for the code to be structurally conservative in the majority of the cases where codon single-base changes result in amino acid substitutions. The possible consequences of this pattern of potential amino acid substitutions are discussed in relation to protein evolutionary processes.

Amino Acids↗