Virus infection of culturable chlorella-like algae and dlevelopment of a plaque assay

Four distinct viruses with double-stranded DNA are known to replicate in Chlorella-like algae symbiotic with hydras and paramecia. An attempt was made to infect a number of cultured Chlorella strains derived from invertebrate hosts with these viruses. One of the viruses, PBCV-1, replicated in two of the algal strains. Restriction endonuclease analysis of the viral DNA showed that the infectious progeny virus was identical to the input virus; thus, Koch's postulates were fulfilled. Viral infection of the two Chlorella strains has allowed the large-scale production of a eukaryotic algal virus and the development of a plaque assay for the virus.     

Vitamin B12 requirement of a marine blue-green alga

A species of Synechocystis isolated from a marine mud has an absolute requirement for vitamin B(12). Analogues of B(12), including cobinamide and alpha-(adenyl) cobamide cyanide, satisfactorily substitute for vitamin B(12). Methionine alone or in combination with other compounds supports only a low level of growth.     

Mesoscale oceanographic processes beneath the ice of fram strait

A major component of the Fram Strait Marginal Ice Zone Experiment was the investigation of air-sea-ice interactions, processes, and circulation patterns found behind the local ice edge and on scales greater than 10 kilometers (mesoscale and large scale). Neutrally buoyant floats, ice-tethered cyclesondes, and helicopter-based measurements were used to obtain uniquely integrated and consistent views of the mesoscale ocean features beneath the ice cover of Fram Strait. Within the vicinity of the Yermak Plateau, three distinct regions of mesoscale motion were observed that coincided with the shallow topography of the plateau, the northward flowing Atlantic water over the western flank of the plateau, and the strong current-shear zone of the East Greenland Polar Front. A subice meander of the front was also observed, which was probably occluded subsequently.     

"Atmospheric" Epoxidation of Benzo[a]pyrene by Ozone: Formation of the Metabolite Benzo[a]pyrene-4,5-Oxide

Benzo[a]pyrene deposited on a glass fiber filter reacts rapidly in the dark or light with ambient levels of ozone to yield a mixture of products that display strong direct mutagenicity in the Ames assay. The major stable contributor to this activity has been identified as benzo[a]pyrene-4,5-oxide, a DNA-binding metabolite in biological systems, known to be a strong direct mutagen with Salmonella typhimurium strain TA98.