khulekani tsese tsese
my bacteria is very interesting because the C-shaped Caulobacter crescentus uses its glue to attach to surfaces in the watery environments where it lives. a team of biologists and physicists measured how much force it took to yank C. crescentus off a surface, it was about 5 tonnes per square inch which is amazing and i love it green color.
It can live in fresh water, salt water and even tap water. It thrives in places where there's almost nothing for it to eat.
this is what a Caulobacter crescentus looks like green and rod shaped
Caulobacter crescentus is a rod-shaped single-celled organism found in fresh water, soil and sea water. Often flourishing in low nutrient environments, this gram-negative bacterium undergoes a dimorphic life cycle that is beneficial in its competitive surroundings. It produces one swimming cell and one sessile cell at each cell cycle. (3,4) Prior to cell division, C. crescentus possesses a stalk (or prosthecae) at one cell pole and a flagellum at the other. Following cytokinesis, the flagellated motile daughter cell (swarmer) swims for about one-third of the cell cycle. The swarmer then sheds its polar flagellum and from the same pole produces an adhesive holdfast. The holdfast, to date the strongest measured biological glue, cements C. crescentus to surfaces in aquatic environments. (2, 5)
C. crescentus cells are curved rods. They divide into two distinct types of cells, division-competent stalked cells and shorter, flagellated swarmer cells that cannot divide. Swarmer cells shed their flagellum and develop into stalked cells before dividing. (1) Ideal growth conditions require the presence of oxygen and organic nutrients in aquatic environments at an optimal temperature of 35ºC. C. crescentus contains a number of energy-dependent transport systems, presumably enabling growth in the substrate-sparse aquatic environments that it lives in. A few other distinguishable characteristics of the C. crescentus include a short stalk, which are known to enhance nutrient uptake, and a surface (S) layer for protection
he presence in C. crescentus of a 20-gene cluster for the metabolism of aromatic compounds, a pathway extensively characterized only in soil bacteria including Pseudomonas and Streptomyces species, highlights a shared biology between this aquatic species and various species of soil bacteria. It also suggests that C. crescentus may be exposed to diverse substrates of terrestrial origin in its natural habitat. As revealed by comparative genome analysis, this shared biology between C. crescentus and soil organisms extends to other cellular processes
due to its distinctive ability to survive in nutrient-limiting conditions, C. crescentus has been selected for extensive studies in broad environmental habitats where contamination may be present. For example, potentially hazardous levels of heavy metals have dispersed into subsurface sediment and groundwater in a number of metal contaminated DOE sites and represent a challenge for environmental restoration. Effective bioremediation of these sites requires knowledge of genetic pathways for resistance and biotransformation by component organisms within a microbial community, including C. crescentus. The recently completed sequence of the strain C. crescentus CB15 has provided the information to study genome wide response to heavy metal stress.
Caulobacters are the most prevalent organisms adapted solely for survival in nutrient-poor aquatic and marine environments. The completion of the genomic sequence now lays the foundation for understanding, on a molecular level, how this bacterium’s obligate differentiation and asymmetric division enable it to thrive in such dilute habitats. Furthermore, the tools developed for genetic manipulation of C. crescentus make it an attractive organism for development as a bioremediation agent.
rod shaped bacteria with a tail
Flagellate seen at 2:20 eventually Neobodo sp.; at 3:00 Rhynchomonas sp., possibly R. nasutaReferences:Quick guide: Caulobacter c...
The swarmer (SW) cell sheds its flagellum (by disassembling the basal rotor) and generates a stalk in its place, attaching to a surface. It then undergoes an asymmetric division to create a new swarmer cell and a stalk cell. And so on, and so on
SW cells must attach to a surface before it can initiate DNA replication (think ORI control!). Two component signal transduction cascades (histidine kinase and a downstream effector) control the process of differentiation.
