Susan Schlimpert

John Innes Centre · Department of Molecular Microbiology

Contractile injection systems (CIS) are bacteriophage tail-like structures that mediate bacterial cell–cell interactions. While CIS are highly abundant across diverse bacterial phyla, representative gene clusters in Gram-positive organisms remain poorly studied. Here we characterize a CIS in the Gram-positive multicellular model organism Streptomyc...

In most bacteria, cell division is orchestrated by the tubulin homolog FtsZ. To ensure the correct placement of the division machinery, FtsZ activity needs to be tightly regulated. Corrales-Guerrero et al. now describe the molecular details of how MipZ, an alphaproteobacterial regulator, interacts with FtsZ to promote proper cell division.

Contractile injection systems (CISs) are bacteriophage tail-like structures that mediate bacterial cell-cell interactions. While CISs are highly abundant across diverse bacterial phyla, representative gene clusters in Gram-positive organisms remain poorly studied. Here we characterize a CIS in the Gram-positive multicellular model organism Streptom...

The transcriptional regulator LexA functions as a repressor of the bacterial SOS response, which is induced under DNA-damaging conditions. This results in the expression of genes important for survival and adaptation.

DNA damage often causes an arrest of the cell cycle that provides time for genome integrity to be restored. In bacteria, the classical SOS DNA damage response leads to an inhibition of cell division resulting in temporarily filamentous growth. This raises the question as to whether such a response mechanism might similarly function in naturally fil...

DNA damage triggers a widely conserved stress response in bacteria called the SOS response that involves two key regulators, the activator RecA and the transcriptional repressor LexA. Despite the wide conservation of the SOS response, the number of genes controlled by LexA varies considerably between different organisms. The filamentous soil-dwelli...

Filamentous actinobacteria such as Streptomyces undergo two distinct modes of cell division, leading to partitioning of growing hyphae into multicellular compartments via cross-walls, and to septation and release of unicellular spores. Specific determinants for cross-wall formation and the importance of hyphal compartmentalization for Streptomyces...

Filamentous actinobacteria like Streptomyces undergo two distinct modes of cell division, leading to the partitioning of growing hyphae into multicellular compartments via cross-walls and to the septation and release of unicellular spores. While some progress has been made towards the regulation of sporulation-specific cell division, specific deter...

For over a decade, Streptomyces venezuelae has been used to study the molecular mechanisms that control morphological development in streptomycetes and it is now a well-established model strain. Its rapid growth and ability to sporulate in a near-synchronised manner in liquid culture, unusual among streptomycetes, greatly facilitates the applicatio...

Bacterial cell division is driven by the polymerization of the GTPase FtsZ into a contractile structure, the so-called Z-ring. This essential process involves proteins that modulate FtsZ dynamics and hence the overall Z-ring architecture. Actinobacteria like Streptomyces and Mycobacterium lack known key FtsZ-regulators. Here we report the identific...

Bacterial cell division is driven by the polymerization of the GTPase FtsZ into a contractile structure, the so-called Z-ring. This essential process involves proteins that modulate FtsZ dynamics and hence the overall Z-ring architecture. Actinobacteria, like Streptomyces and Mycobacterium lack known key FtsZ-regulators. Here we report the identifi...

Significance Bacterial dynamins were discovered ∼10 y ago and the explosion in genome sequencing has shown that they radiate throughout the bacteria, being present in >1,000 species. In eukaryotes, dynamins play critical roles in the detachment of endocytic vesicles from the plasma membrane, the division of chloroplasts and peroxisomes, and both th...

Live-cell imaging of biological processes at the single cell level has been instrumental to our current understanding of the subcellular organization of bacterial cells. However, the application of time-lapse microscopy to study the cell biological processes underpinning development in the sporulating filamentous bacteria Streptomyces has been hamp...

The complex life cycle of streptomycetes involves two distinct filamentous cell forms: the growing (or vegetative) hyphae and the reproductive (or aerial) hyphae, which differentiate into long chains of spores. Until recently, little was known about the signalling pathways that regulate the developmental transitions leading to sporulation. In this...

The alphaproteobacterium Hyphomonas neptunium proliferates by a unique budding mechanism in which daughter cells emerge from the end of a stalk-like extension emanating from the mother cell body. Studies of this species so far have been hampered by the lack of a genetic system and of molecular tools allowing the regulated expression of target genes...

The cyclic dinucleotide c-di-GMP is a signaling molecule with diverse functions in cellular physiology. Here, we report that c-di-GMP can assemble into a tetramer that mediates the effective dimerization of a transcription factor, BldD, which controls the progression of multicellular differentiation in sporulating actinomycete bacteria. BldD repres...

The Gram-negative bacterium Caulobacter crescentus forms a thin polar stalk, which mediates its attachment to solid surfaces. Whereas stalks remain short (1 µm) in nutrient-rich conditions, they lengthen dramatically (up to 30 µm) upon phosphate starvation. A long-standing hypothesis is that the Caulobacter stalk functions as a nutrient scavenging...

Bacterial cell division involves the dynamic assembly of division proteins and coordinated constriction of the cell envelope. A wide range of factors regulates cell division-including growth and environmental stresses-and the targeting of the division machinery has been a widely discussed approach for antimicrobial therapies. This paper introduces...

In eukaryotes, the differentiation of cellular extensions such as cilia or neuronal axons depends on the partitioning of proteins to distinct plasma membrane domains by specialized diffusion barriers. However, examples of this compartmentalization strategy are still missing for prokaryotes, although complex cellular architectures are also widesprea...

In bacteria, cytokinesis is dependent on lytic enzymes that facilitate remodelling of the cell wall during constriction. In this work, we identify a thus far uncharacterized periplasmic protein, DipM, that is required for cell division and polarity in Caulobacter crescentus. DipM is composed of four peptidoglycan binding (LysM) domains and a C-term...