Histone-organized chromatin in bacteria

Hocher, Antoine; Laursen, Shawn; Radford, Paul M.; Tyson, Jess; Lambert, Carey; Stevens, Kathryn M; Picardeau, Mathieu; Sockett, R. Elizabeth; Luger, Karolin; Warnecke, Tobias

doi:10.1101/2023.01.26.525422

Cited by 7 publications

(10 citation statements)

References 52 publications

(95 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, our findings also show that HBb is essential for maintaining bacterial viability. These results are consistent with a recent preprint published on bioRxiv, which reports the structure of the HBb-DNA complex and proposes a role for HBb in genome organization (Hocher et al, 2023).…”

Section: Introductionsupporting

confidence: 92%

“…To understand the functional significance of HBb, we attempted to construct a strain in which the hbb gene (BD_RS00255) was replaced by a kanamycin resistance cassette. However, we were unable to select for the loss of the gene, suggesting that HBb is essential for B. bacteriovorus during the growth phase, as also shown in a recent study (Hocher et al, 2023). These results provide compelling evidence for the critical role of HBb in the growth and survival of B. bacteriovorus.…”

Section: Hbb Binds Dna In Vitro and Is Essential For Growthsupporting

confidence: 76%

“…However, unlike archaeal and eukaryotic histones, recent research has shown that HBb does not form nucleosome-like structures, but that HBb dimers form a sheath around straight DNA (Hocher et al, 2023). Futhermore, we found that HBb is indispensable for the survival of B. bacteriovorus, suggesting that bacterial histones, much like their counterparts in archaea and eukaryotes, are likely involved in critical cellular functions.…”

Section: Discussionmentioning

confidence: 57%

“…3c). This value is considerably lower than the nanomolar DNA-binding affinities determined for other histone homologs (Bailey et al, 2002, indicating that HBb likely binds to DNA non-specifically via a different type of interaction, as was shown recently (Hocher et al, 2023).…”

Section: Hbb Binds Dna In Vitro and Is Essential For Growthmentioning

confidence: 59%

“…This suggests that HBb likely binds DNA, but possibly in a different manner than HMfB. Indeed, an HBb-DNA complex reported in a recent preprint suggests that HBb binds DNA differently than archaeal and eukaryotic histones (Hocher et al, 2023).…”

Section: Crystal Structure Of Hbbmentioning

confidence: 99%

See 4 more Smart Citations

Bacterial histone HBb fromBdellovibrio bacteriovoruscompacts DNA by bending

Hu¹,

Deiss²,

Joiner³

et al. 2023

Preprint

View full text Add to dashboard Cite

Histones are DNA-binding proteins that play a crucial role in DNA packaging and gene regulation in eukaryotes and archaea. In eukaryotes, histones form octamers that constitute the core of the nucleosome, the fundamental unit of chromatin. Archaeal histones, on the other hand, form tetramers that assemble into extended superhelices upon DNA binding. Although previously thought to occur only in archaea and eukaryotes, histone homologs have recently been discovered in bacteria. This work presents the dimeric crystal structure of the bacterial histone HBb from Bdellovibrio bacteriovorus determined at a resolution of 1.06 Angstrom, representing the first-ever structure of any histone protein determined at atomic resolution. Furthermore, this study shows that HBb binds DNA and is essential for bacterial viability, suggesting that bacterial histone homologs likely have a similar biological function as their eukaryotic and archaeal counterparts. These findings have important implications for our understanding of the fundamental processes of DNA organization and regulation in all domains of life.

show abstract

Section: Introductionsupporting

confidence: 92%

Section: Hbb Binds Dna In Vitro and Is Essential For Growthsupporting

confidence: 76%

Section: Discussionmentioning

confidence: 57%

Section: Hbb Binds Dna In Vitro and Is Essential For Growthmentioning

confidence: 59%

Section: Crystal Structure Of Hbbmentioning

confidence: 99%

See 3 more Smart Citations

Bacterial histone HBb fromBdellovibrio bacteriovoruscompacts DNA by bending

Hu¹,

Deiss²,

Joiner³

et al. 2023

Preprint

View full text Add to dashboard Cite

show abstract

Dogma-defying bacteria package DNA in unusual ways

Ledford¹

2023

Nature

View full text Add to dashboard Cite

DNA-bridging by an archaeal histone variant via a unique tetramerisation interface

Ofer,

Blombach,

Erkelens

et al. 2023

Commun Biol

View full text Add to dashboard Cite

In eukaryotes, histone paralogues form obligate heterodimers such as H3/H4 and H2A/H2B that assemble into octameric nucleosome particles. Archaeal histones are dimeric and assemble on DNA into ‘hypernucleosome’ particles of varying sizes with each dimer wrapping 30 bp of DNA. These are composed of canonical and variant histone paralogues, but the function of these variants is poorly understood. Here, we characterise the structure and function of the histone paralogue MJ1647 from Methanocaldococcus jannaschii that has a unique C-terminal extension enabling homotetramerisation. The 1.9 Å X-ray structure of a dimeric MJ1647 species, structural modelling of the tetramer, and site-directed mutagenesis reveal that the C-terminal tetramerization module consists of two alpha helices in a handshake arrangement. Unlike canonical histones, MJ1647 tetramers can bridge two DNA molecules in vitro. Using single-molecule tethered particle motion and DNA binding assays, we show that MJ1647 tetramers bind ~60 bp DNA and compact DNA in a highly cooperative manner. We furthermore show that MJ1647 effectively competes with the transcription machinery to block access to the promoter in vitro. To the best of our knowledge, MJ1647 is the first histone shown to have DNA bridging properties, which has important implications for genome structure and gene expression in archaea.

show abstract

Histone-organized chromatin in bacteria

Cited by 7 publications

References 52 publications

Bacterial histone HBb fromBdellovibrio bacteriovoruscompacts DNA by bending

Bacterial histone HBb fromBdellovibrio bacteriovoruscompacts DNA by bending

Dogma-defying bacteria package DNA in unusual ways

DNA-bridging by an archaeal histone variant via a unique tetramerisation interface

Contact Info

Product

Resources

About