Exploring the diversity of mechanosensitive channels in bacterial genomes
- PDF / 844,787 Bytes
- 12 Pages / 595.276 x 790.866 pts Page_size
- 70 Downloads / 223 Views
ORIGINAL ARTICLE
Exploring the diversity of mechanosensitive channels in bacterial genomes Sarah C. Johnson1 · Jordyn Veres1 · Hannah R. Malcolm1 Received: 30 June 2020 / Revised: 8 October 2020 / Accepted: 8 November 2020 © European Biophysical Societies’ Association 2020
Abstract Mechanosensitive ion channels are responsible for touch sensation and proprioception in higher level organisms such as humans and recovery after osmotic stress in bacteria. Bacterial mechanosensitive channels are homologous to either the mechanosensitive channel of large conductance (MscL) or the mechanosensitive channel of small conductance (MscS). In the E. coli genome there are seven unique mechanosensitive channels, a single MscL homologue, and six MscS homologues. The six MscS homologues are members of the diverse MscS superfamily of ion channels, and these channels show variation on both the N and C termini when compared to E. coli MscS. In bacterial strains with phenotypic analysis of the endogenous mechanosensors, the quantity of MscS superfamily members in the genome range from 2 to 6 and all of the strains contain a copy of MscL. Here, we show an in-depth analysis of over 150 diverse bacterial genomes, encompassing nine phyla, to determine the number of genomes that contain an MscL homologue and the average number of MscS superfamily members per genome. We determined that the average genome contains 4 ± 3 MscS homologues and 67% of bacterial genomes encode for a MscL homologue. Keywords Mechanosensitive ion channels · MscS superfamily · MscL · Bacterial ion channels
Introduction Mechanosensitive ion channels are found in all cell types. In bacteria, one of their key roles is to rescue cells from hypoosmotic shock by relieving pressure in the membrane (Blount and Iscla 2020; Booth and Blount 2012; Booth et al. 2015; Cox et al. 2018). In response to a buildup of tension in the membrane, mechanosensitive ion channels will open a pore in the membrane of the cell in order to relieve the pressure. In bacterial membranes, two distinct mechanosensitive phenotypes have been observed: a small conductance channel and a large conductance channel. The Sarah C. Johnson and Jordyn Veres contributed equally to this work. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s00249-020-01478-1) contains supplementary material, which is available to authorized users. * Hannah R. Malcolm [email protected] 1
Department of Chemistry, University of North Florida, Jacksonville, FL, USA
‘small’ conductance channel opens at a lower tension than the ‘large’ conductance channel. In some bacterial membranes a smaller ‘mini’ conductance channel is observed. The most well-studied bacterial mechanosensitive channels are found in Escherichia coli (E. coli) membranes, the mechanosensitive channel of small conductance (MscS), and and the mechanosensitive channel of large conductance (MscL). These two channels were phenotypically identified based on the size of the pores they open in the cell membrane to
Data Loading...
