The primates of the Baly Bay area, north-western Madagascar.

Primate surveys were conducted in isolated primary west Malagasy decidous forest blocks around Baly Bay, north-western Madagascar. Eight species of primate were found, including Microcebus c.f. myoxinus, Hapalemur griseus occidentalis and Phaner furcifer. Two species were found only in Namoroka Strict Nature Reserve, which may mean that other forest blocks in the area have experienced primate extinctions. The record of M. c.f. myoxinus came from mangrove, the first confirmed record of a lemur from this habitat. The pelage of female Eulemur fulvus rufus was atypical.

Differential distribution of D and L amino acids between the 2' and 3' positions of the AMP residue at the 3' terminus of transfer ribonucleic acid.

Amino acids esterified to the ribose group of 5'-adenylic acid (AMP) constantly migrate between the 2' and 3' positions of the ribose at a rate of several times per second, which is slower than the rate of peptide-bond synthesis (15-20 per sec). Because the contemporary protein-synthesizing system only incorporates amino acids into protein when they are at the 3' position of the AMP at the terminus of tRNA, the value of the equilibrium constant relative to the 2' and 3' positions is of considerable interest. Differences between D and L isomers in this regard might be especially revealing. We have used N-acetylaminoacyl esters of AMP as models for the 3' terminus of tRNA and find that glycine and the L amino acids consistently distribute predominantly to the 3' position (approximately equal to 67% 3', approximately equal to 33% 2'), but D amino acids distribute to that position generally to a lesser extent and in a manner inversely related to the hydrophobicity of the amino acid side chain. This consistency of the L amino acid preference for the 3' position, combined with the inconsistency of the D amino acid preference, may be one reason for the origin of our contemporary protein-synthesizing system, which forms the peptide bond preferentially with L amino acids and only when they are in the 3' position of the ribose moiety of the AMP residue at the 3' terminus of every tRNA.