Viral Plasmacytosis (Aleutian Disease) of Mink Resembling Human Collagen Disease

A disease in mink has been discovered that has many of the features of collagen diseases in man. Affected animals suffer from wasting with leukopenia and thrombocytopenia as well as plasma cell infiltration, hypergammaglobulinemia, glomerulonephritis, arteritis and amyloidosis. Cell-free filtrates and ultracentrifugates from diseased animals induced the disease in normal mink, and aleutian genotypes were unusually susceptible to infection. This genotype was characterized by abnormal lysosomal structures in all the granule-forming cells, resembling the Chediak-Higashi syndrome of man. Anti-γ-globulin factors similar to human rheumatoid factors were reported, although tests for antibodies such as ANF and LE factors have been negative. Arteritis and glomerulonephritis lesions stained positively for γ-globulin, and Coombs-type sensitized red cells have been detected in the majority of affected mink. Some mink develop a monodispersion of hypergammaglobulinemia resembling the serum protein changes in human myeloma. These studies highlight genetic, immunological and microbiological causative factors in a mink disorder resembling human collagen disease.     

The folate-binding protein of rat kidney. Purification, properties, and cellular distribution

Folate-binding protein (FBP) from rat kidney was isolated, and its properties and location in the kidney were determined. The particulate fraction of rat kidney homogenate was freed of its bound folate, solubilized with Triton X-100, and the FBP was purified using a combination of DEAE-cellulose and affinity chromatography. The purified protein migrated as a single band on sodium dodecyl sulfate-disc gel electrophoresis, has an isoelectric point of 5.7, contains 21.7% carbohydrate, and has an Mr of 28,500-30,000. The purified protein retained its affinities for different folate derivatives and its sensitivity to inorganic anions. Inorganic anions enhanced the binding of 5-methyltetrahydrofolate; chloride ion was the most effective, followed by Br- greater than I- greater than SO2-4. Chloride ion was also found to lower the dissociation constant of the folic acid-FBP complex at 50 degrees C by about 10-fold. This effect is thought to derive from the formation of a ternary FBP-folic acid-Cl- complex which is more stable than the binary FBP-folic acid complex. An antiserum raised against the purified protein in rabbits was used to determine the location of FBP in the kidney by immunofluorescence. Intense fluorescence staining for FBP was localized at the apices (brush border) of proximal tubules. The choroid plexus, an organ previously shown to contain FBP, also exhibited intense fluorescent staining.     

16S and 23S plastid rDNA phylogenies of Prototheca species and their auxanographic phenotypes

Because algae have become more accepted as sources of human nutrition, phylogenetic analysis can help resolve the taxonomy of taxa that have not been well studied. This can help establish algal evolutionary relationships. Here, we compare Auxenochlorella protothecoides and 23 strains of Prototheca based on their complete 16S and partial 23S plastid rDNA sequences along with nutrient utilization (auxanographic) profiles. These data demonstrate that some of the species groupings are not in agreement with the molecular phylogenetic analyses and that auxanographic profiles are poor predictors of phylogenetic relationships.