Synthesis of Two Natural Salmon Calcitonins

The structure of calcitonin isolated from salmon¹ (SCT 1) has been recently established² and confirmed by synthesis⁸. It possesses an exceptionally high level of activity, exhibiting about 20–50 times the hypocalcaemic potency of any other calcitonin isolated from mammalian species.     

A Carlavirus and a Rhabdovirus Infecting Lonicera X brownii cv. Dropmore Scarlet in Western Canada

Chlorotic and necrotic spots, yellow mottle, and vein banding leaf symptoms were seen on two honeysuckle vines in the Botanical Garden, University of British Columbia. Electron microscopic examination showed the presence of rhabdovirus and carlavirus particles. This is the first report of a rhabdovirus in honeysuckle. The carlavirus may be honeysuckle latent virus, although it was transmitted to only three of its nine reported herbaceous hosts, and it was not transmitted by the reported aphid vector, Hydaphis foeniculi . Both types of virus particles were seen in mesophyll, phloem parenchyma and companion cells of honeysuckle. The rhabdovirus was not transmitted to any other host and, in honeysuckle, was found only in the Spring. As its concentration declined, the number of carlavirus particles increased.     

Hatching of the winter eggs of the fruit-tree red spider mite (Panonychus ulmi (Koch))

Observations on the hatching of winter eggs of Panonychus ulmi (Koch) from apple orchards in England over the 5 years 1962-6 are described. Differences of 2–3 weeks between orchards in the date at which 50% hatch was reached were quite common and this was out of step with petal fall in the majority of orchards. There was a continuous range between early and late hatching populations and a tendency for the populations to hatch in the same order every year. In 1966 populations on Cox's Orange Pippin hatched earlier than those on Worcester Pearmain but the difference was unlikely to be of practical importance. Neither recording accumulated day degrees for populations hatched out-of-doors nor hatching in an incubator after chilling was considered to give a sufficiently reliable forecast of 50% hatch but observations in 1966 suggested that this might be predicted from the total eggs hatched in an incubator expressed as a percentage of total healthy eggs.     

Monograph of the genus Brighamia (Lobeliaceae).Hawaiian Plant Studies 29

The Hawaiian genus Brighamia (Lobeliaceae) was published in 1868 as monotypic, and it long remained so, even though it occurs on four islandS. It is a spectacular herb with a simple, thickened, fleshy, stem 1–5 m tall, with the leaves terminal and crowded, and subtended by them are the fragrant, salver-shaped flowers 12–15 cm in length. Further explorations have revealed new localities, mostly on the cliff faces of the windward sides of the islands. The present investigation has revealed significant differential characters in the calyx lobes, the flower colour, the hairiness of the filament tube and the anther connective, and the nature of the seed testa. Hence, the following new taxa are described: B.citrina var. napaliensis, B.rockii and B.rockii forma longiloba and B.remyi.     

Plant growth-regulators

Large-scale use of plant growth-regulating chemicals, unheard of ten years ago, has fostered a multimillion dollar business. In 1948, 27 1/2 million pounds of 2,4-D, once used only in minute doses for laboratory work, were manufactured for agricultural use, primarily in weed eradication. Naphthaleneacetic acid and other compounds are used in smaller but continually increasing quantities in regulating other phases of plant development, wholly apart from nutritional needs supplied by fertilizers.     

Stereochemistry of the acyl dihydroxyacetone phosphate acyl exchange reaction

The fatty acid of acyl dihydroxyacetone phosphate can be exchanged enzymatically for another fatty acid. It has been shown that this reaction proceeds by cleavage of the oxygen bound to C-1 of the dihydroxyacetone phosphate (DHAP) moiety rather than by the more common cleavage at the acyl to oxygen bond. In the present study, the stereochemistry of this reaction was defined further; using deuterated substrates and fast atom bombardment-mass spectrometry, it was shown that the fatty acid exchange involves the stereospecific labilization of the pro-R hydrogen at C-1 of the DHAP moiety of acyl DHAP. The mechanism of ether bond formation, in which acyl DHAP is converted to O-alkyl DHAP, also proceeds via labilization of the pro-R hydrogen and cleavage of the fatty acid at the C-1 to oxygen bond. In addition, other workers have provided evidence that the enzyme responsible for the exchange reaction is O-alkyl DHAP synthetase. Therefore, the present results support the hypothesis that the acyl exchange is the reverse reaction of the first step in O-alkyl DHAP synthesis; in both of these reactions the pro-R hydrogen of C-1 of the DHAP moiety of acyl DHAP and the fatty acid moiety are labilized with cleavage of the fatty acid at the DHAP C-1 to oxygen bond.