The stereochemistry of hydrogen transfer to NADP+ by enzymes acting upon stereoisomeric substrates

The stereochemistry of hydrogen transfer from estradiol-17α and estradiol-17β to NADP⁺ in the presence of chicken liver estradiol-17α and estradiol-17β dehydrogenases was found in both cases to involve the 4-pro-S proton of the pyridine nucleotide. One of these enzymes must therefore use the stereochemically less favorable mode of interaction of steroid with coenzyme.     

The pattern of loci on Drosophila chromosomes.

In this study, we have attempted to detect and describe patterns in the arrangement of gene loci within chromosomes of a metazoon. Known loci (842 of them) on the first three chromosomes of Drosophila melanogaster have been characterised according to a list of 45 properties and the distributions of these properties have been examined systematically. For all these properties, there is little, if any, evidence of clustering between known loci that are not close enough to belong to the same 10-locus group. Our analysis has, however, revealed evidence confirming that some properties show a tendency to cluster within a 10-locus group. Even this tendency is not strong, except for some of the morphological properties. However, it is apparently at variance with the findings of Elston and Glassman (1967), based on fewer data.