Morphology of transcriptionally active chromatin.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to H Zentgraf.
Explore the source record for details and available documents.
Herpes simplex virus type 1 (HSV-1), strain ANG, was passaged serially at high MOI or undiluted on RC-37 cells. The yields of infectious virus decreased and increased periodically with a maximum of about 3 log units variation in titer. The amount of newly synthesized HSV-1 DNA, however, did not vary by more than a factor of 2. On the other hand, the fraction of total HSV-1 DNA associated with virions was reduced at passage numbers coinciding with the minima in the yields of infectious progeny virus. Apparently, low yields of infectious virus mainly reflected a reduced efficiency of packaging of viral DNA into mature virus particles. One step in the process of virus maturation which appeared to be impaired was the assembly of nucleocapsids. HSV-1 ang was shown to be capable of generating different classes of defective particle in independent series of virus passages at high MOI.
Explore the source record for details and available documents.
Three DNA binding proteins from Escherichia coli cells have been complexed with single-stranded phage fd DNA. Electron microscopy reveals granular substructures in the complexes formed with protein HD. In complexes of DNA unwinding protein with fd DNA both protein HD and phage-coded gene 5 protein partially displace the unwinding protein which results in the formation of structures characteristic for the DNA complexes formed with either protein HD or gene 5 protein alone. Combination of protein HD with double-stranded phage T7 DNA leads to a progressive folding and condensing of the genome. The structures observed are discussed in relation to current concepts of the packing of DNA in protein complexes.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The structure of integrated hepatitis B virus (HBV) DNA was analysed to determine the origin of recurrent and multinodular hepatocellular carcinoma (HCC). In 5 cases, recurrent tumours were compared with the respective primary tumours, all of which had chromosomally integrated viral DNA. In only one of these cases, an identical HBV DNA integration pattern was found, indicating a monocentric origin of primary and secondary tumour. In all other cases a polycentric origin was deduced. Particular features observed were: (i) the apparent absence of integrated viral DNA in a recurrent tumour; and (ii) an integration pattern identical to that of the primary tumour and a distinct new pattern in two different foci of multinodular recurrent HCC. For multinodular primary HCC one case was analysed and found to be of independent origin.