Menaquinone and Iron Are Essential for Complex Colony Development in Bacillus subtilis

Gidi Pelchovich,Shira Omer-Bendori,Uri Gophna,Adam Driks

doi:10.1371/journal.pone.0079488

Abstract

Cells of undomesticated species of Bacillus subtilis frequently form complex colonies during spreading on agar surfaces. Given that menaquinone is involved in another form of coordinated behavior, namely, sporulation, we looked for a possible role for menaquinone in complex colony development (CCD) in the B. subtilis strain NCIB 3610. Here we show that inhibition of menaquinone biosynthesis in B. subtilis indeed abolished its ability to develop complex colonies. Additionally some mutations of B. subtilis which confer defective CCD could be suppressed by menaquinone derivatives. Several such mutants mapped to the dhb operon encoding the genes responsible for the biosynthesis of the iron siderophore, bacillibactin. Our results demonstrate that both menaquinone and iron are essential for CCD in B. subtilis.

Highlights

In nature, when confronted with difficult environmental conditions, groups of bacterial cells enter a physiological state that conveys new traits to the group and relies on a programmed collaboration between large numbers of cells [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17]
Menaquinone is required for complex colony development in the B. subtilis 3610
Complex colony development is a social form of motility that enables bacteria to travel and colonize solid surfaces [1,5,28,29,30,31,32,33,34,35,36,37,38,39,69]

Summary

Introduction

In nature, when confronted with difficult environmental conditions, groups of bacterial cells enter a physiological state that conveys new traits to the group and relies on a programmed collaboration between large numbers of cells [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17] This collaboration, is known as multicellularity [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18], and involves sophisticated modes of intercellular communication such as cell-cell physical interactions, long term chemical signals and chemotaxis [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18]. These microenvironments lead to differential gene expression and the development of different cell types in specific areas of the colony [1,15,32,33,36,38,43,44]

Methods

Results

Conclusion