The word
"flagellum" refers to a long, whip-like tail or appendage that certain microorganisms, like bacteria or sperm, use for movement.
Full definition
Dr Hideyuki Matsunami of the Trans - Membrane Trafficking Unit at the Okinawa Institute of Science and Technology Graduate University (OIST), together with a team of scientists, explored some aspects of the formation
of flagella in research that may have implications for contrasting bacterial infections.
For he spoke long before William Dembski began stringing out his texts with all those ones and zeros, and long before Michael Behe began instructing the lay public in the intricacies of
bacterial flagella.
Bacteria propel by pushing against the tiny fluid corkscrew - like appendages
called flagella.
The bacteria's whip -
like flagella help keep the robot suspended in the fluid environment while also providing a small bit of forward propulsion.
Assisted in assembly of the bacterial
flagellum in Gram - negative bacteria, principally Salmonella enterica.
Nearly half of the samples contained cells
with flagella, tail - like projections that sperm use to swim.
But the real surprise was that it had genes
for flagella, tails bacteria use to propel themselves, which basically means it could be swimming around in the environment.
Nature's inventions could inspire new biomedical solutions such as nanorobots propelled
by flagella systems in the direction provided by their magnetosome chain.
Many bacteria swim
using flagella — long tails that are attached to tiny motors made of proteins, just tens of nanometres wide.
The
sperm flagellum of the fruit fly Drosophila melanogaster appears as a good model to study the genetic regulation of axoneme assembly and motility, due to the wealth of genetic tools publically available for this organism.
Described as «raisin - like» in appearance under the microscope, M. jannaschii has a thin, tail - like
flagellum on one end that gives the cell mobility.
The similarity in names is no accident, for these are single - celled creatures, with
whiplike flagella surrounded by a collar of microvilli, and they bear an amazing resemblance to the choanocyte cells of sponges.
Inspired by nature's nanomachines — such as the enzyme ATP synthase and the motor -
driven flagella of bacteria — physicists in Prof. Hendrik Dietz's lab at TUM keep expanding their own design and construction repertoire.
But although growing
several flagella allowed the bacteria to efficiently cover the entire surface, the adaptation also left them less able to stick together tightly and form biofilms.
Algae in this genus have a cell wall, a chloroplast, an «eye» that perceives light, and two
anterior flagella with which they can swim using a breast - stroke type motion.
Coupled with the long, sensing whip - like
flagella extending from the tip of the claws, this makes the frontal appendages of the animal some of the most versatile and complex in all known arthropods.
According to the researchers» calculations, reported this week in Physical Review Letters, the colonies»
flagella generate currents that interact with the top and bottom of the tank to create eddies of water.
It has two tiers of armor: a petal - like arrangement of vertical plates overlying an interior layer of ribbed oval disks.The center area is where a
tiny flagellum will grow, allowing it some mobility but not against a current.
When looking at bacteria, you typically see
also flagella: long hairs that protrudes from the bacteria's body.
Importantly, there is large overlap in the receptive fields of neighboring neurons, which ensures complete coverage over the
entire flagellum.
With individual polymer molecules roughly the same size as a single bacterium, the bacteria's
flagella physically stretch out the coiled - up polymers like a rubber band.
Michael Eisenbach and Martin Welch who work at the Weizmann Institute of Science in Rehovot, Israel, and Kenji Oosawa and Shin - Ichi Aizawa of Teikyo University in Japan, have studied a bacterium that has between 6 and 12
flagella spread randomly over the cell surface.
With the help of a
wiggling flagellum and a variable number of googly eyes, you dart forth into the primordial soup.
But changing lifestyles is as easy as cashing in DNA for a new mouth — or if you prefer, multiple mouths — along with
extra flagella, defensive spikes, poison - spewing vesicles, and other organismic add - ons.
Flagellar motors can spin much faster than that — up to 1700 Hertz — although of
course flagella are smaller and lighter than the helix.
Children in developing countries have probably been exposed to
more flagella - carrying bacteria when they are vaccinated, he says.
Oddly enough, centrioles, the structures responsible for cell division and
flagella movement, are given by the paternal gamete.
What they didn't know was how tubulin and another cell organelle known
as flagella fit into the process.
In addition, the fruit fly's sperm
flagellum displays quite a long axoneme (∼ 1.8 mm), which may facilitate both histological and biochemical analyses.
Several bird species have evolved faster sperm cells that typically have longer midpieces, where the mitochondria are stored;
longer flagella; and / or relatively small heads.
Choanoflagellates are not the most charismatic of creatures, consisting of an oval blob equipped with a single
taillike flagellum that propels the organism through the water and also allows it to eat.
During sperm biogenesis,
flagella appear tightly bundled, which makes it more challenging to get accurate measurements of protein levels from immunostained specimens.
Isla San Ildefonso has four species of reptile:
Coluber flagellum (coachwhip), Phyllodactylus nocticolus (peninsular leaf - toed gecko), Sceloporus orcutti (granite spiny lizard), and Uta stansburiana (common side - blotched lizard).
According to new research, tiny colonies of the common algae Volvox can whirl each other around for hours like ballroom dancers, driven by the rhythm of tiny, tail - like structures
called flagella.
The researchers identified genes
for flagella and for chemotaxis, the process of moving purposefully toward a chemical.
The cytoskeleton maintains cellular structure, builds appendages
like flagella and, together with motor proteins, powers cellular movement, transport, and division.
Known as Chlamy to researchers, this alga's combination of traits — it has a cell wall and chloroplasts, but also an eyespot and pair
of flagella, and switches between sunlight and carbon for food — has made it a popular study subject for decades.
Dinoflagellates like Peridinium furca are best known for two transparent
whiplike flagella — one that encircles the body, the other arising from between the two points.
The team aims to understand how cilia /
flagella assembly is controlled during mouse and Drosophila development and what underlies cilia diversity.
Here, we present a protocol for imaging and quantitatively analyze proteins, which associate with the fly differentiating, and mature
sperm flagella.