Cover Page
The handle
http://hdl.handle.net/1887/75618
holds various files of this Leiden University
dissertation.
Author: Ramijan, Carmiol A.K.
Title: Off the wall: characterisation and exploitation of a cell wall-deficient life style in
filamentous actinomycetes
Stellingen
Propositions accompanying this thesis
Off the wall: characterisation and exploitation of a cell
wall-deficient life style in filamentous actinomycetes
1. Formation of wall-deficient cells by actinomycetes and their subsequent switch to the filamentous mode-of-growth creates genetic and
morphological diversity
Chapter 2 and 3 of this thesis
2. In filamentous actinomycetes the morphological switch to wall deficiency is a transient adaptation to osmotic stress
Chapter 3 of this thesis
3. Transition from a walled to a permanent wall-deficient state requires genetic changes
Chapter 3 of this thesis
4. L-forms are powerful to identify requirements for cell wall synthesis
Chapter 4 of this thesis
5. Actinomycetes L-forms can secrete functional Tat substrates
Chapter 5 of this thesis
6. In bacteria the switch to a cell wall-deficient state is an escape from stress
Slavchev et al, New Microbiol 2013, Monahan et al, Antimicrob Agent Chemother 2014, Kawai et al Cell 2018, and this thesis
7. L-form variants of all bacteria proliferate in a similar manner, driven by membrane dynamics and independent of cell division machinery
Leaver et al, Nature 2009, Dell’Era et al Mol Microbiol 2009, Mercier et al, eLife 2014, Ramjian et al, Nat Comms 2018
8. In filamentous actinomycetes cell division is dispensable for vegetative growth but incorporation of cell wall is essential
McCormick et al, Mol Microbiol 1994, McCormick Opin Microbiol 2009, Santos-Beneit et al
Nat Comms 2017, Flärdh Mol Microbiol 2003, and the chapter 4 of this thesis
9. Deletions of the right chromosomal arm and loss of megaplasmids in cell wall-deficient cells, challenges the concept that loci with cellular primary functions are exclusively located in the chromosomal core region
Bentley et al, Nature 2002, Medema et al, Genome Biol Evol 2010, Kinashi J. Antibiot 2011, and this thesis.
11. To overcome the impostor syndrome, no one should understand your work better than you.
12. The statement from Groucho Marx “If you're not having fun, you're doing something wrong”, is what should define if your research is going in a good direction.
