Essay on Intestinal Vesicle of Nematodes

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S. carpocapsae and X. nematophila are mutualistic symbionts that parasitize, kill and use insects for reproduction. S. carpocapsae develop into non-feeding infective juveniles (IJ’s). The S. c. IJ’s serve as vectors for the X. n. The vector IJ’s then colonize at a place termed the vesicle. X. n. are released from the vesicle, via nematode defecation, into a new insect host. This process serves as a model to understand general aspects of horizontal transmission of symbionts by their hosts. It takes very few X. n. cells that are retained in the intestinal vesicle to initiate colonization of S. c.
Microbial attachment to host tissues plays an important role in the initiation of pathogenic and nonpathogenic microbe-host
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The lumen can also refer to the inner membrane space of cellular molecules such as chloroplasts, Golgi apparatuses, and mitochondria.

The intravesicular structure (IVS) is an “untethered cluster of anucleate spherical bodies”. In laymen’s terms, the IVS consists of molecular structures that contain no nucleus.

In the case of nematodes, the lumen is the basic lining of the intestines where colocalization occurs. The colonizing bacteria continue to grow until their discharge is stimulated by insect haemolymph.

Haemolymph is defined as the circulatory fluid of certain invertebrates; it is analogous to blood in arthropods and to lymph in other invertebrates.

In this process, the insect haemolymph causes the anal release of X. nematophila that have colonized its IVS. It was also shown that in the absence of colonizing bacteria, the nematode still secretes its IVS. This process of secretion also expels the excess X. nematophila that have not attached to the vesicle.

In order for the S. carpocapsae to colonize and grow more efficiently, the presence of adequate X. nematophila bacteria is necessary. The hypothesis is that the creation of more than 85% of S. carpocapsae utilizes X. nematophila. The remaining 15% of the population was assumed to have continued colonizing at a much slower pace.

While X. nematophila colocalize with colonizing S. carpocapsae, they do not require the bacteria to exist. This

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