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Assume that the bacteria, which you are interested in studying, is unculturable in the lab environment. How could you still experimentally determine the presebce of this bacterial genus in an environmental sample? Explain how you may establish an uncultured organism's evolutionary relationship to other organisms on a 16S rRNA phylogenetic tree? Would there be any limitations with that approach?

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13 Dec 2019
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The Case of the Paralyzed Gardener. Part 2.

Katie, Julia's girlfriend, was really scared now. In addition to having trouble opening her eyes and slurring her words, Julia could now hardly walk or sit up. Katie called an ambulance, and they rushed Julia to the hospital. Due to the sudden onset and the neurological nature of the signs and symptoms, the doctor tested Julia for a stroke.

Fortunately, the results came back negative. Since Julia could not speak, the doctor began asking Katie questions about her partner's health, habits, and lifestyle. Eventually, it came up that Julia frequented farmers markets and had recently consumed some vegetables she canned at home. Upon hearing about the home canning, the doctor immediately suspected botulism. Clostridium botulinum bacteria are common in soil, so they can easily contaminate vegetables, and improper canning is a known risk factor for exposure. Although the doctor knew that the collected blood and stool samples may contain the bacterium and/or the botulinum toxin, the results would take several days to obtain, and Julia didn't have days to wait. Based on mounting suspicion, the doctor ordered an electromyography study, which confirmed that Julia's muscles and nerves were not working properly. Because botulism is a nationally reportable disease, the physician immediately contacted the local health department and, in collaboration with the U.S. Centers for Disease Control and Prevention, coordinated delivery of the antitoxin that was needed to save Julia's life.

Several days later, the lab confirmed that botulinum toxin was found in Julia's blood samples and, C. botulinum was grown from stool samples. It was a good thing the doctor had reacted so swiftly to obtain the antitoxin. Though the doctor had identified the cause of the illness, the source of the bacteria was still not confirmed. Was it food from the market? Her canned goods? Somewhere else? When placed in a stressful environment like soil, this bacterium sporulates, forming hardy structures called endospores that can survive for decades. The low oxygen and low acid environment that occurs in certain canned vegetables can allow the endospores to germinate, leading to toxin production.

Since Julia was new to canning, Katie suspected that it was the beans and corn. She mentioned this point to the doctor, who requested a can of each to send to the health department for confirmation. At the lab, the technicians did some basic staining and growth to see if there was bacterial contamination. Though the identification was not definitive, they were able to grow Gram-positive bacilli from Julia's canned food.

QUESTION 1: The process of canning vegetables involves high heat and, sometimes, low pH to kill contaminating microorganisms. How do you think these might prevent bacterial growth? Select all that apply. (NCLEX style)

A.Degrading sugars used as microbial food sources
B. Denaturing proteins
C. Altering quaternary structures

D. Destroying cell membranes

QUESTION 2: When an animal's gastrointestinal tract is colonized with C. botulinum, the causative agent of botulism, the bacteria secretes a neurotoxin, which moves into the bloodstream and down its concentration gradient without help from any external energy or proteins. Which of the following terms correctly describes this sort of molecular movement?

A.Osmosis
B. Facilitated diffusion
C. Active transport
D. Simple diffusion

Asexual reproduction: the first step to extinction
When species become asexual they could be taking the first stepto
extinction, say researchers who have been studying the geneticstructure
of Penicillium marneffei, an asexual fungus only found in parts ofsouth­
east Asia. Their research found that although P. marneffei sporeswere
able to spread over large distances on currents of air, they werenot able
to ‘invade’ the new environments in which they landed.
‘We believe the failure of P. marneffei to adapt to newenvironments is
because the fungus has largely dispensed with sexualreproduction.
Without sex, you will not have the mixing of genes it causes,something
all organisms need in order to be able to adapt to newenvironments’, said
a member of the research team. Evolutionary theory predicts thatwhile
asexual organisms can initially prosper and out-compete theirsexual
cousins, they pay a price for being unable to adapt throughthe
recombination of genes caused by sexual reproduction.
DNA typing was used to show that different clones of the fungusare
found in different environments, and the researchers believe thatthe
adaptation of the fungus to these environments is limiting theirability to
adapt to other areas. They believe this is why P. marneffei isonly
endemic to a relatively small area of south-east Asia. Even thoughthe
6_________________________________________________________________
fungus makes spores which can spread over very large distances,the
researchers found that all the samples from any given locationwere
genetically very similar. This led them to the conclusion that thefungus
becomes highly adapted to its local environment, making ithighly
successful there, but stopping it spreading to other areas.
‘By being asexual, P. marneffei is not only limiting its ability toadapt, it
may be at risk of becoming extinct. If it is unable to adapt tonew
environments, it will be unable to adapt to changes in itscurrent
environment. While becoming asexual may provide short term
advantages to a species, in the long term, they are likely to endup in
evolution’s ultimate dustbin – extinction’, concluded a member ofthe
research team

You should introduce your article by very briefly explaining thepurpose of
biological reproduction and touching upon the strategies used toachieve it, then
write your account using the following list as a guide to thepoints you should
discuss in your answer:
? How does asexual reproduction differ from sexual reproduction interms of
the biological processes involved and the genetic diversity andvariation of
the DNA produced?
What are the advantages and disadvantages of asexual andsexual
reproduction?
In terms of survival and adaptation, which reproduction strategy ismore
likely to allow a species to evolve rapidly (or to become extinct)?In your
answer briefly describe the two main mechanisms used to creategenetic
variation. Also, explain the factors and pressures that are likelyto drive the
process of adaptation.

For this assignment, Part One of your course project, assume the role of Dr. Madness. Your rogue nation seeks global domination. With a bare bones laboratory and your exhaustive microbiological and epidemiological knowledge, you (Dr. Madness) decide that the best way to rule the world is to create and disseminate the perfect biological weapon.

For this part of the assignment, you will develop your weapon from the ground up. Discuss nearly all of the epidemiological criteria related to it, and justify and discuss why it is used and how effective it is. This agent could be a hybrid of other biological pathogens or an entirely new one. If the agent is newly created, there must be some basis and epidemiological support of a similar agent by which you can base your justification. In other words, it will be unrealistic to create an airborne virus that inoculates and kills within one hour. There must be a realistic exposure and incubation time and must be supported through current agent biology or biochemistry (for example, influenza exposure and incubation takes 1–4 days).

Name of Agent: Explain why you chose the name. If it is a biological agent, be sure to provide a taxonomic name

Etiology: This will talk about the genesis of your agent. Where was it discovered? How was it made? How long has it been around? Why was this agent created? What were the social and economic factors of your rogue nation that made Dr. Madness focus on this element of the agent? What are the environmental precursors to this agent? Discuss the interaction among agent, host, and environment.

Identification: This will describe the basics of the agent. Is it a bacteria, virus, toxin, parasite, hybrid, or something else? Discuss how your agent presents within the human population. What are the symptoms in humans? What are the (zoonotic) symptoms in animals? How does the disease progress? Are there stages? Discuss the various stages including length of infection, severity, and the like. What are the diagnostic indicators? How would a doctor be able to identify this agent in a clinic or emergency room?

Laboratory Analysis: How will the agent be identified? Can it be grown in media? What type of laboratory methods can be used to identify the agent (microscopy, chromatography, PCR, and so on)?

Occurrence: This is the epi: who, what, when, where, how, and why of the disease. Where does it happen? When can it be found? Who is most and least susceptible to the agent (risk factors). More exotic and hard to find agents are harder to prevent and control but are also more difficult to initiate an epidemic or pandemic, whereas more generalized and known agents may be easier to cure, but have a much wider swath of causing pandemics. How do socioeconomic factors foster or inhibit the spread of disease?

Reservoir: What is the natural reservoir of the agent? Are there other organisms where this agent can reside without causing disease? Increasing the reservoir can enhance transmission but can also allow for easier identification and treatment in response to it.

Mode of Transmission: Consider inhalation, absorption, digestion, contact, and so forth. If you use multiple modes, justify your selections.

Incubation Period: Provide the range with an average (median) day of disease onset. Does the period change in different socioeconomic status identifiers (sex, age, race, creed, and so on)? Why or why not?

Period of communicability: How long is a person with this agent contagious? Increasing this period also increases the opportunity for study and thus treatment and control.

Susceptibility: Is the agent susceptible to reinfection of the same person? Allowing for this increases morbidity but usually mortality wanes in subsequent infections.

Taking on the role of Dr. Madness, generate your superweapon and describe the weapon using the above mentioned criteria. Remember, the focus in on creating something that becomes difficult to identify, monitor, or treat with prophylaxis. You will write out the proposal as Dr. Madness submitting this to his lead researcher to develop. This proposal should be approximately 6–8 pages in length, but some submissions may be longer.

Submit your Bioweapons and Epidemiology Part One proposal in the assignment area.

Please be sure to review the Bioweapons and Epidemiology Part One Scoring Guide for information on how this assignment is graded.

Project Requirements

To achieve a successful project experience and outcome, you are expected to meet the following requirements.

Written communication: Written communication is free of errors that detract from the overall message.

APA formatting: Resources and citations should be formatted according to current APA style and formatting.

Resources: Include all literature cited in the project.

Length of paper: 6–8 typed, single-spaced pages, not including cover page and resource list.

Font and font size: Arial, 10 point.

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