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A stereoselective total synthesis of nat (−) prostaglandin E 1 and its optical antipode employing the Diels-Alder adduct of trans -piperylene and maleic anhydride as starting material is described.

The carbohydrate composition of an IgA (α1 subtype) myeloma protein has been determined. The carbohydrate, present only on the heavy chain, was found to consist of 3 moles of sialic acid, 9 mole of galactose, 5.4 moles of mannose, 0.8 moles of fucose, 8.8 moles of N-acetylglucosamine, and 5 moles of N-acetylgalactosamine per mole of heavy chain. Four major glycopeptide-containing fractions were isolated following pronase degradation of the protein. Glycopeptide I consisted of galactose, N-acetylgalactosamine, threonine, serine, and proline in the molar ratio 4:5:4:5:9. Each of the N-acetylgalactosamine residues was found to be involved in an O-glycosidic linkage, demonstrating that there are five O-glycosidically linked oligosaccharide units per heavy chain. The structure of this glycopeptide is presented in the following paper (Baenziger, J., and Kornfeld, S. (1974) J. Biol. Chem. 249, 7270–7281. The three other glycopeptide fractions contained 1 to 2 residues of sialic acid, 0 to 0.7 residue of fucose, 2 residues of galactose, 3 residues of mannose, 4 to 5 residues of N-acetylglucosamine, and 1 residue of asparagine. Glycopeptide IIA was a homogeneous glycopeptide with the following structure: Glycopeptide fractions IIB and IIC did not appear to be homogeneous, but instead each contained 2 glycopeptides. In both cases, one of the glycopeptides was probably the disialyl form of IIA containing a residue of sialic acid linked α2,6 to the terminal galactose. The other glycopeptide had 2 rather than 3 nonreducing termini arising from the core mannose. Both of these terminated in sialic acid and had the same sequence as that found for the sialic acid-containing terminus of IIA. These termini arose from positions 3 and 6 of the core mannose. The core of this glycopeptide differed from that of IIA in having a residue of fucose which was most likely linked α1,6 to the N-acetylglucosamine involved in the N-glycosidic linkage to the peptide.

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Mycodextranase is an α-glucanase which splits only the α-1,4 linkages in a substrate having alternating α-1,3 and α-1,4 links. It ïs a fungal enzyme of rather infrequent occurrence, adaptive in nature, and in its properties strongly resembling other fungal glucanases. The products of its action on mycodextran are a tetramer and nigerose. The hypothesis is advanced that this glucanase, and others, contain a site which binds a dimeric portion of the polymer; in mycodextranase, the bound dimer is nigerose, the α-1,3-disaccharide.

Six α-amylases (MAR, NAT, NA20, NA64, SAC and LIQ) produced by a transformable strain of Bacillus subtilis 6160, by a DNA donor strain of Bacillus natto IAM 1212, by representative transformants Bacillus subtilis NA20 and NA64, by Bacillus subtilis var. amylosacchariticus and Bacillus amyloliquefaciens F were compared with one another with regard to their immunological and chemical properties, including peptide mappings. Five α-amylases (MAR, NAT, NA20, NA64 and SAC) cross-reacted almost equally with rabbit anti α-amylase (SAC) serum but not with rabbit anti α-amylase (LIQ) serum, α-Amylases (MAR and NA64) contained about 9% of carbohydrate but not the others. The different indices calculated from the amino acid compositions showed not only structural similarity among the five α-amylases but also considerable difference between them. More than 80% of the tryptic peptide components from α-amylases (MAR and NA64) seemed to be identical and 4 or 5 specific peptides for each were detected. About 88% of the tryptic peptides from α-amylase (NAT) seemed to be in common with those from α-amylase (NA20). The latter contained more specific peptides than the former. The peptide maps of the five saccharifying type α-amylases (MAR, NAT, NA20, NA64 and SAC) showed that at least 12 peptides seemed to be common.

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The second Indian embassy to Rome was the consequence of an accident. Pliny tells the story thus. A freedman of one Annius Plocamus, while in the Red Sea collecting the tolls and customs farmed of Claudius by his patron, was caught in a gale of wind, driven past Carmania, and on the fifteenth day carried into Hippuros, a port of Ceylon. Here, though his ship with its contents seems to have been seized and confiscated to the king's use, he himself was kindly and hospitably treated. In six months' time he learned the language. Admitted to familiar intercourse with the king, in answer to his questions he told him of Rome and of Cæsar. In these conversations and from some denarii which had been found in the Roman ship, and which from the heads upon them had evidently been coined at different times and by different persons, and which nevertheless were all of the same weight, the Singhalese monarch learned to appreciate Roman justice. He became desirous of forming an alliance with Rome, and to that purpose sent over one Rachias with three other ambassadors to Claudius. And from their statements Pliny intimates that he derived that fuller and more accurate information with respect to Ceylon which he has embodied in his Natural History.