Welcome to Haloferax volcanii

Introduction

H. volcanii is a model organism for the halophilic archaea (Haloarchaea) due to the ease of cultivation under laboratory conditions and numerous established genetic and biochemical methods (for a review see (1)).

H. volcanii is an euryarchaeon of the family Halobacteriaceae isolated from the Dead Sea and named after Benjamin Elazari Volcani (2-3). Halobacteriaceae are "salt-loving" archaea that require saturated or nearly saturated NaCl solutions for growth, H. volcanii prefers a salt concentration of 2.2 M NaCl.

The outer cell envelope consists of a so-called "surface layer" (S-layer), which is composed of a glycoprotein. The red colour of the cells is due to carotenoids (bacterioruberins) incorporated into the cell membrane. The GC-rich (65%) genome is completely sequenced and, with a total size of about 4.1 Mb, is composed of a major chromosome (2.9 Mb), the three chromosomal plasmids pHV1 (85 kb), pHV3 (438 kb), pHV4 (636 kb) and the non-essential plasmid pHV2 (6.4 kb) (4). The circular DNA molecules are present in multiple copies in the cell (5).

H. volcanii is a chemoorganotrophic organism that can use various carbohydrates, glycerol and organic acids as energy sources under aerobic conditions, the optimal growth temperature is between 42 ℃ and 45 ℃.

So far, H. volcanii genome has not yet been analysed broadly with a dedicated focus on small proteins. We generated a translatome map for H. volcanii based on Ribosome profiling (Ribo-seq) in collaboration with prof. Anita Marchfelder (Ulm University).

Here we present a JBrowse instance to browse the Ribo-seq data and the catalog of small proteins identified in the model archaeon Haloferax volcanii.

Publication

The publication describing this project can be accessed via the following DOI: https://doi.org/10.1093/femsml/uqad001

Data availability

The raw sequencing data used in this study can be accessed via the GEO accession number GSE208086.

The Mass spectrometry data is available on ProteomeXchange: PXD031423 (annotated sORFs), PXD031691 (novel sORFs) and PXD031460 (spectral-library based validation)

The processed files used in this JBrowse2 genome browser can be downloaded here.

JBrowse2

Access Area

Default session

Annotation tracks

We provide multiple annotation tracks for the H. volcanii genome.
All annotation files can be loaded and unloaded using their respective check box in the track selector.
Annotation files are indexed and specific genes can be searched by gene name, locus tag or gene id using the search box in the top center of the JBrowse2 instance.
This JBrowse2 instance includes:

Track Description
The Reference Annotation The reference annotation for Haloferax volcanii
DeepRibo Predictions A list of ORF predictions created using the tool DeepRibo.
List of novel sORFs A list of 47 novel sORFs identified by Ribo-seq.
Start Codon Motifs All ATG motifs for the reference genome.
Alternative Start Codon Motifs All GTG and TTG motifs for the reference genome.
Stop Codon Motifs All TAA, TAG and TGA motifs for the reference genome.

Coverage tracks

Coverage tracks show the normalized read counts per nucleotide position. There are multiple mapping types used (threeprime/fiveprime/global). The mapping method of each file is marked in their description.

Shareable Links

JBrowse2 allows you to easily share observations with your colleagues and collaborators.
Using the "share"-button next to the session name, you can automatically generate a link. Anyone that uses this link will see the exact session you are currently looking at. This includes colors, zoom level, scale, loaded tracks etc...
This is a very powerful tool for sharing potential discoveries.

JBrowse2 user guide

For more information on how to use JBrowse2, please have a look at the comprehensive user guide provided by the JBrowse team. The chapter on basic usage is highly recommended to get familiar with the JBrowse2 interface.

Contributors

This project is a collaboration between the universities of Ulm, Würzburg, Greifswald and Freiburg.

AG Marchfelder
  • Prof. Dr. Anita Marchfelder
  • Dr. Lisa-Katharina Maier
  • Verena Vogel
AG Becher
  • Prof. Dr. Dörte Becher
  • Dr. Sandra Maaß
  • Jürgen Bartel
AG Sharma
  • Prof. Cynthia Sharma
  • Dr. Lydia Hadjeras
AG Backofen
  • Prof. Rolf Backofen
  • Rick Gelhausen

References

  1. Leigh JA, Albers SV, Atomi H, Allers T (2011) Model organisms for genetics in the domain Archaea: methanogens, halophiles, Thermococcales and Sulfolobales. FEMS Microbiol Rev 35: 577–608
    https://doi.org/10.1111/j.1574-6976.2011.00265.x
  2. Mullakhanbhai MF, Larsen H (1975) Halobacterium volcanii spec. nov., a Dead Sea halobacterium with a moderate salt requirement. Arch Microbiol 104: 207–14
    https://doi.org/10.1007/bf00447326
  3. Oren A (2006) The order halobacteriales. In The Prokaryotes, M D, S F, E R, K–H S, E S (eds) pp 113 – 164. Springer.
    https://link.springer.com/referenceworkentry/10.1007/0-387-30743-5_8
  4. Hartman AL, Norais Cd, Badger JH, Delmas Sp, Haldenby S, Madupu R, Robinson J, Khouri H, Ren Q, Lowe TM, –Maupin–Furlow J, Pohlschroder M, Daniels C, Pfeiffer F, Allers T, Eisen JA (2010) The Complete Genome Sequence of Haloferax volcanii DS2, a Model Archaeon. PLoS ONE 5: e9605
    https://doi.org/10.1371/journal.pone.0009605
  5. Breuert S, Allers T, Spohn G, Soppa J (2006) Regulated polyploidy in halophilic archaea. PLoS One 1: e92
    https://doi.org/10.1371/journal.pone.0000092