Nucleoid Condensation in Escherichia coli That Express a Chlamydial Histone Homolog

See allHide authors and affiliations

Science  17 Apr 1992:
Vol. 256, Issue 5055, pp. 377-379
DOI: 10.1126/science.256.5055.377


Chlamydial cell types are adapted for either extracellular survival or intracellular growth. In the transcriptionally inert elementary bodies, the chromosome is densely compacted; in metabolically active reticulate bodies, the chromatin is loosely organized. Condensation of the chlamydial nucleoid occurs concomitant with expression of proteins homologous to eukaryotic histone H1. When the Chlamydia trachomatis 18-kilodalton histone homolog Hc1 is expressed in Escherichia coli, a condensed nucleoid structure similar to that of chlamydiae is observed with both light and electron microscopy. These results support a role for Hc1 in condensation of the chlamydial nucleoid.

Stay Connected to Science