Isolation and characterization of chromatin from XXXX .

@entity1522 @entity535 @entity1980 @entity2975 @entity291
Different preparations of chromatin isolated from mycelia of @entity1980 were analyzed for DNA-associated RNA and proteins. The UV absorption spectra, the ultrastructure of chromatin, and the @entity535 composition of the acid-extractable proteins were studied. The protein:DNA ratios range from 1.5 to 2.8; the RNA:DNA ratios range from 0.5 to 1.24. UV absorption shows a macimum at 259 mmicro and a minimum at 238-239 mmicro. The E280/E260 ranges from 0.59 to 0.70. Electron microscopy reveals a fibrous structure with individual fibers of 120-150 A average diameter. Attempts were made to study the protein by @entity2975 gel electrophoresis and @entity535 analysis. The results indicate that @entity1980 chromatin does not contain basic proteins comparable to @entity291 thymus histone. The ratios of basic to acidic @entity1522 range from 0.93 to 1.19. On electrophoresis, no bands are seen whose positions correspond to those of histones. Staining for basic proteins with fast green or eosin Y at pH 8.2 also shows a negative reaction, suggesting the absence of histones.
