Metabolite profiling and peptidoglycan analysis of transient cell wall-deficient bacteria in a new Escherichia coli model system.
Environ Microbiol
; 17(5): 1586-99, 2015 May.
Article
em En
| MEDLINE
| ID: mdl-25142185
ABSTRACT
Many bacteria are able to assume a transient cell wall-deficient (or L-form) state under favourable osmotic conditions. Cell wall stress such as exposure to ß-lactam antibiotics can enforce the transition to and maintenance of this state. L-forms actively proliferate and can return to the walled state upon removal of the inducing agent. We have adopted Escherichia coli as a model system for the controlled transition to and reversion from the L-form state, and have studied these dynamics with genetics, cell biology and 'omics' technologies. As such, a transposon mutagenesis screen underscored the requirement for the Rcs phosphorelay and colanic acid synthesis, while proteomics show only little differences between rods and L-forms. In contrast, metabolome comparison reveals the high abundance of lysophospholipids and phospholipids with unsaturated or cyclopropanized fatty acids in E. coliâ
L-forms. This increase of membrane lipids associated with increased membrane fluidity may facilitate proliferation through bud formation. Visualization of the residual peptidoglycan with a fluorescently labelled peptidoglycan binding protein indicates de novo cell wall synthesis and a role for septal peptidoglycan synthesis during bud constriction. The DD-carboxypeptidases PBP5 and PBP6 are threefold and fourfold upregulated in L-forms, indicating a specific role for regulation of crosslinking during L-form proliferation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptidoglicano
/
Parede Celular
/
Escherichia coli
/
Lipídeos de Membrana
Idioma:
En
Revista:
Environ Microbiol
Assunto da revista:
MICROBIOLOGIA
/
SAUDE AMBIENTAL
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Bélgica