"Photorhabdus and Xenorhabdus bacteria colonize the intestines of the infective soil-dwelling stage of entomophagous nematodes, Heterorhabditis and Steinernema, respectively. These nematodes infect susceptible insect larvae and release the bacteria into the insect blood. The bacteria kill the insect larvae and convert the cadaver into a food source suitable for nematode growth and development. After several rounds of reproduction the nematodes are recolonized by the bacteria before emerging from the insect cadaver into the soil to search for a new host.
"Photorhabdus and Xenorhabdus bacteria therefore engage in both pathogenic and mutualistic interactions with different invertebrate hosts as obligate components of their life cycle." (Goodrich-Blair and Clarke)
If none of that made sense to you, then you’re on the right track. This paper provides a simple, yet comprehensive understanding of the research taking place in the laboratory of a scientist by the name of Dr. Patricia Stock. Her aim is to study the symbiotic relationship between nematodes and the bacteria they host while further developing ideas of their mutualism, pathogenesis and evolutionary biology.
At first glance, her research may seem irrelevent to the modern world. You may ask yourself: What does the relationship between a parasitic nematode and the bacteria inside it have anything to do with my life? Truth be told, it potentially has a lot to do with the preservation of your life. Their relationship will "shed further light on the fundamental mechanisms controlling the interactions, and their outcomes, between bacteria and their hosts." (Goodrich-Blair and Clarke) The bacteria alone release chemical compounds potentially capable of producing prescription d...
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... further research and development, but the necessary tools were scarce.
Dr. Patricia Stock’s particular area of study does not include the biochemical investigation of their composition to find their chemical usefulness or the cure for cancer or anything of that nature. Her aim is simply to research and study the mutuality between the bacteria and their nematode hosts in order to better understand their evolutionary biology and pathogenesis.
Although on a regular basis she relays her discoveries to other scientists interested more in the utilization of their chemical composition, Dr. Stock’s passion remains in the biology of these overlooked but fascinating organisms.
Sources
Goodrich-Blair, Heidi and Clarke, David J. (2007) Mutualism and pathogenesis in Xenorhabdus and Photorhabdus: two roads to the same destination. Molecular Microbiology 64 (2): 264-268
Jennifer Ackerman's main focus in her article The Ultimate Social Network, is that of the functions concerning bacteria within humans. Although scientists have had presumptions about humans being proficient in governing their body’s innermost structure, they soon come to recognize the sophistication of our inner space which holds an extensive plethora of bacteria and other microorganisms that lie within each and every one of us. Moreover, scientists' new and emerging view of how the human body operates, and the cause of increasing present-day diseases (i.e. obesity and different autoimmune disorders) are uncovered by analyzing effects of certain microbe species in our bodies. By italicizing on points such as the above, in conjunction with bacteria's genetic variations, and modern computing technology, the author proves that scientists are quickly progressing with the characterization the most prevalent species of microbes, which, in her opinion, is definitely paying off.
Her dreams of being a scientist came true as she worked hard to achieve her degree and make startling discoveries. Among her accomplishments she made the discovery of isozymes of kynurenine formamidase in the basterium streptomyces parvulus which, prior to her findings, were known to only exist in higher organisms. Dr. Emeagwali also proved that cancer gene expression could be inhibited by antisense methodology, which she says can lead to better treatment for cancer. She is a well-accredited scientist that many people have never heard of. All fields of science affect the lives of many people, but the inventors are left out.
Bacteria play a large role in our health, the environment, and most aspects of life. They can be used in beneficial ways, such as decomposing wastes, enhancing fertilizer for crops, and breaking down of substances that our bodies cannot. However, many bacteria can also be very harmful by causing disease. Understanding how to identify bacteria has numerous applications and is incredibly important for anyone planning to enter the medical field or begin a career in research. Having the background knowledge of identifying an unknown bacteria may one day aid healthcare professionals diagnose their patient with a particular bacterial infection or help researchers determine various clinical, agricultural, and numerous other uses for bacteria.
Silver-haired Bat - Lasionycteris noctivagans . 26 Jan. 1998. The University of New Mexico . 21 Feb. 2004 .
The basis for the symbiotic relationship in these species is complex. The infection of the host cell by rhizobia occurs within the plant’s root nodules. Bacteroides, gram-negative anaerobic bacteria, are isolated from the host cell by a peribacteroid membrane; the membrane between the plasma membrane of the cell and the membrane of the bacteroid. The bacteroid contains differentiated rhizobia, which are able to fix nitrogen due to the supply of carbon from the host plant. Sucrose is delivered to the nodules of the root via the phloem, where it is cleaved by suc synthase, and enters the Krebs cycle. The product of glyco...
Kopp, Elizabeth, and Medzhitov, Ruslan. “A Plague on Host Defense.” The Journal of Experimental Medicine. .
Disease and parasitism play a pervasive role in all life. Many of these diseases start with microparasites, which are characterized by their ability to reproduce directly within an individual host. They are also characterized by their small size, short duration of infection, and the production of an immune response in infected and recovered individuals. Microparasites which damage hosts in the course of their association are recognized as pathogens. The level of the interaction and the extent of the resultant damage depends on both the virulence of the pathogen, as well as the host defenses. If the pathogen can overcome the host defenses, the host will be damaged and may not survive. If on the other hand the host defenses overcome the pathogen, the microparasite may fail to establish itself within the host and die.
Naegleria fowleri, the brain eating amoeba, exists around the world; reservoirs of N fowleri include sediments of lakes, rivers, geothermal water, soil, and poorly kept swimming pools. These microbes can live in temperatures up to 45 degree Celsius and do not require a host cell for survival. The free-living amoeba is the etiological source of primary amoebic meningeocephalitis (PAM), an acute and fatal disease of the central nervous system with fatality rates over 99%. Onset of illness is quick and death typically occurs within 7-14 days. Treatment for PAM poses a challenge because of rapid disease progression and limited awareness among clinicians. According to the CDC, there are more than 30 species of Naegleria that exist, however, N fowleri is exclusively the species recognized to be pathogenic in humans. When conditions are favorable, this free-living amoeba can survive outside of the host cell.
Bethany Halford’s article, Rapamycin's Secrets Unearthed, explores the discovery and how the research rapamycin has led science today. In 1964, a group of scientists departed for a Canadian expedition to study the people who lived in Easter Island that were immune to tetanus (a bacterial infection) by collecting 67 samples of soil for analyses1. By 1969, only one of the 67 samples were able to be further analyzed which unknowingly contained rapamycin1. More so, the name rapamycin came from Rapa Nui, which was the name given to the people of Easter Island1. Furthermore, rapamycin was seen as a potential compound that can further cancer research because it’s antifungal activity, potent immunosuppressant ability, and could contain cells from multiplying.
Audesirk, Teresa, Gerald Audesirk, and Bruce E. Byers. Biology: Life on Earth with Physiology. Upper Saddle River, NJ: Pearson Education, 2011. 268-69. Print.
The Bt spores then leak from the gut and germinate in the insect, causing death within a few days.
It is noticed that science develops in splashes, each significantly advancing our understanding of the nature. The 19th century was the time of rapid development of microbiology. In the search for secrets of nature science has reached extremely high and low energies as well as large and small length scales. Still until recently we knew very little about one of the most complex aspects of life – microbes and infection. Now we are at the dawn of efflorescence in molecular biology, which provides an excellent basis for application into several areas of biology like cancer and virology . Revelations of molecular biology become extremely crucial, as they provide insights into the way molecules work.
Microbes are everywhere in the biosphere, and their presence invariably affects the environment in which they grow. The effects
T. pallidum is highly sensitive to oxygen and has a decreased ability to survive when not in human body temperature environments 1. The mode of transmission is through sexual contact or vertical transmission from the mother to the fetus. T. pallidum lacks the lipopolysaccharide which is the endotoxin normally present in gram negative bacteria1. The bacterium does produce many lipoproteins which are thought to prompt the inflammatory mediators through the recognition of toll-like receptors1. T. pallidum has a virulence factor of being highly motile due to its ability to propel itself forward by rotating on a longitudinal axis1. The spirochetes easily penetrate the skin or mucosal membranes and spread throughout the lymph nodes and then the blood circulation, affecting many parts in the body1.