Biochemical Aspects of Genetics.

It would be impossible, in the time and space available, to cover all of the noteworthy advances that have been made in biochemical genetics during the past year. We have, therefore, selected for review a number of topics that are especially active at the moment and that promise to yield important new results in the near future. At the same time, we have tried to avoid duplicating the material of other chapters in this volume ~vhich are germane to biochemical genetics. We refer, in particular, to the chapters on Metabolism of Nucleic Acids (Macromolecular D NA and RNA) ; Nucleic Acids and Protein Biosynthesis; The Basic Proteins of Cell Nuclei; and Chemistry of Differentiation in Lower Organisms. The reader should consult these reviews, as well as the present one, for a fuller view of current activities in this field. By way of introduction, we should like to call attention to some papers of general interest. The formation of animal viruses in bacterial cells infected with viral DNA has been reported from two laboratories. Abel & Trautner (1) first showed that DNA prepared from vacclnla virus is capable of infecting Bacillus sublilis and giving rise to complete virus particles. This result was confirmed by Bayreuther & Romig (2), who found that DNA from polyoma virus also infects B. subtilis, with the production of complete virus. Since, in both cases, formation of virus particles involves the synthesis of serologically specific coat proteins, these results constitute compelling evidence for universality of the genetic code. A curious sidelight to these findings has been the rediscovery of a series of papers published in the ’thirties by Silber and co-workers in Moscow, in which the growth of pox, herpes, and other animal viruses in yeast and bacteria was described [see (3, 4) and subsequent papers in the same journal]3 A fundamental advance has been made simultaneously by Yanofsky et al. (5), working with the A protein of E. coli tryptophan synthetase, and by Sarabhai et al. (6), with the head protein of bacteriophage T4D. Both groups of workers proved colinearity of the gene with its cognate protein. Roberts (7) has studied an unusual series of mutants in Aspergillus. The genes control utilization of sorbitol and are unusual in that they show complementation in trans-heterozygous diploids but not in heterocaryons. The 1 The literature survey for this review was completed in October 1964. ~ We are indebted to Dr. K. E. Bayreuther for these references.