Microbiology is the study of organisms that are too small to be seen with the naked eye. This includes organisms like bacteria, fungi, protozoa, and others.

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The damage of cancer cells

I read about the molecular biology of cancer, and I have a mess on my head and a lot of questions.. . My primary question is- The damage of the cancer cells is in the dna sequence or in the gene ...
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1k views

What are the differences between G+ and G- bacteria?

The distinction between Gram-positive and Gram-negative bacteria is based upon the Gram staining method, that reflects the bacterial wall physical properties. However, this classification involves ...
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What are some places where biofilms could develop? [closed]

I'm trying to think of places where a biofilm could develop other than on medical equipment or food processing equipment such as stainless steel mechanized blades or knives. I'm thinking more along ...
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141 views

Why would yeast grow but not produce alcohol?

I'm studying for my intro to microbiology test and I have a question asking why a culture of yeast responsible for producing alcohol would be growing, but not producing alcohol? The multiple choice ...
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31 views

Difference between Fulminant and Acute Meningococcemias

Fulminant seems to mead rapid. There is however some articles with both phrases: "fulminant meningococcecemia" (about 5000 Google matches) and "acute meningococcecemia" (about 3000 Google matches). I ...
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Do Yersinia genus spp have anything movement factors?

It can spread in blood (Type III secretion system -> apoptosis). I am interested if there is any others ways to move. Do Yersinia spp have anything virulence factors to move?
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To understand clearly extraintestinal diseases

Extradistestinal disease seems to prefer to "bowel" diseases, I think this is about diseases outside gastrointestinal tract so stomach. Consider diseases ulcerative colitis and Crohn's disease ...
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35 views

Staphylococcus AG structure?

I found this statement in my study materials in the section of Staphylococcus The AG structure: protein AG (species specific); polysaccharide AG (serotype specific). I know what is ...
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128 views

Lineage selection in plasmid evolution

I've been reading through Paulsson (2002) and I am not sure what he means by "lineage selection" in the second to last section. The paper deals with plasmid replication, and mostly concentrates on the ...
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257 views

Would two species of yeast with similar genome sizes have the same number of genes or chromosomes?

Similar organisms generally have similar genome sizes. Given this, would two species of yeast have the same number of genes and chromosomes? Edit: Fixed with thanks to @daniel-standage
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106 views

Growing E. coli at room temperature?

If I were to do a blue/white selection of transformed E. coli on LB agar ampicillin plates at room temperature (23⁰C) for about 2 days and 18 hours, will I run into the issue of satellite colonies or ...
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75 views

What is the expected effect of pH on the activity of a fungal pectinase?

I am working on an enzyme assay for a fungal pectinase.I assayed the enzyme in different buffers from pH 1-12.5 However,the enzyme has good activities starting from pH1-10.5. Is it possible to have ...
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74 views

Can Alzheimer's disease be caused by Slow Prion infection?

I found this claim in my study materials with explanation of amyloi plaques, in comparison to CJD (Creutzfeldt-Jakob Disease). Its characteristic are Long doubling time of at least 5.2 days (I ...
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49 views

Any forms of pneumonia that can be caught?

I am aware of the fact that there are several different types of pneumonia. However, I am wondering if any of these types of pneumonia are contagious from person to person. Is this possible?
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31 views

To have TBE vaccine during allergic times with mild asthmatic symptoms?

My assistant says that if you have asthmatic symptoms you cannot have TBE (Tick Born Encephalitis) vaccine, although you are living in the active zone of TBE. Cases mild allergic symptoms allergic ...
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1answer
118 views

How do Gram + bacteria use a proton gradient for F-type ATPase?

Does anyone know of any papers showing how Gram positive Fermiculates or Actinobacteria use a H+ gradient for an F-type ATPase, It seems impossible since there is no outer LPS membrane to maintain ...
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218 views

How does activation of adenylcyclase lead to increased cAMP and diarrhea?

I am trying find explanation for these mechanisms Tox plasmid -> exotoxin (enterotoxin) -> activation of adenylcyclase -> \up cAMP enterocytes -> release of H2O, electrolytes in gut lumen -> ...
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74 views

Why does sulfonamid not inhibit the growth of Rickettsia?

Sulfonamid is an antimicrobial agent, why has it no effect on the growth of Rickettsia?
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116 views

explanation of conjugation experiment in bacteria

In this paper (On the expression of a structural gene) I am confused about what is being plotted in Figure 6. The x-axis contains the fraction of radioactive day and y-axis contains the enzyme ...
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56 views

Is this necrotizing skin infection caused by Staphylococcus aureus?

A 5-year-old boy returns from summer camp with several minor cuts and abrasions on legs. He has fever and extensive cellulitis, subcutaneous tissue and muscles are involved. Necrotic tissues were ...
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117 views

Is this case Histoplasma capsulatum?

A 62­ year-­old male was admitted to the hospital complaining of shortness of breath. His chest X­-ray showed a rightsided cavitary lesions. His medical history indicated he had smoked one pack of ...
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1answer
40 views

Do toxin producing strains of E. coli constantly produce toxin or only under certain conditions?

Background E. coli is prevalent everywhere but only some strains produce toxins harmful to humans, such as E. coli O157:H7. Questions 1) Would anyone know if these strains are always producing ...
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89 views

Colonial Cells Demonstrating Cell Specialization

Are there any living examples of cellular colonies demonstrating very primitive cellular specialization? If so, what do we know about how they assimilate? How independent are the individual cells ...
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16 views

Ways to cause membrane damage to microalgae and yeast?

I am researching a way to monitor the membrane damage of cells. To do that I fist have to have reference points, namely, cells with damaged membranes. I am working with Dunalliela, Hematococcus (both ...
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21 views

Why are plasmid genes not already incorporated into bacterial chromosomes if necessary for stressful situations?

If plasmids are important for bacteria to express specific genes under stressful conditions, why are these genes not already incorporated into their chromosome to begin with? What is the evolutionary ...
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38 views

How can I isolate live Wolbachia endosymbionts from Drosophila [closed]

I am interested to culture Wolbachia bacteria in cell line.
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48 views

Optimization of E. coli growth in D₂O (heavy water)

I would like to find a method of increasing the biomass of my D2O cultures because my current method is not yielding enough protein. I would like to also minimize the amount of H2O in my culture. My ...
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1answer
60 views

Molecular Cloning- Blunt end restriction endonucleases

I work in a microbiology lab where we do a lot of cloning. I have always used restriction endonucleases to cleave the DNA to have sticky ends and not blunt ends. I currently am working on a project ...
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29 views

What is the specific use of a capsule in E.coli?

In evolutionary terms, will the capsule cease to exist someday or will it improve ? Does it provide any boost to the organism in any way which harms us ? Can't we remove capsules or engineer E.coli ...
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70 views

How do penicillin resistant bacteria grow slower in the presence of penicillin?

We put 2 flasks inoculated with Bacillus cereus in 37⁰C: one with 100μg/ml penicillin + 50μg/ml chloramphenicol and the other without penicillin. We found that the OD is higher in the one without the ...
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37 views

Cells created using differently aligned proteins

I remember reading that scientist were making cells (I assume bacteria), that used differently oriented proteins to create a whole new class of life. Because apparently right and left aligned proteins ...
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188 views

Can SIRS occur without Sepsis from Infection?

I am thinking this figure It suggests me that there has to be Sepsis that infection can lead to SIRS. I am thinking particularly the pathogenesis of Cryptococcus neoformans where respiratory ...
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51 views

How does HBeAg change to Anti-HBe in acute hepatitis

I am thinking this figure which can also be drawn like this How does HBeAg change to Anti-HBe? There are some triggers that stimulate Anti-HBe production after HBeAg level is done. I think ...
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2answers
52 views

What's the fastest legal way for the nutrients in a dead body to re-enter the ecosystem?

Apologies for weirdness. Of the various legal methods of disposing of a human corpse, which one ensures the nutrients which compose the body get back into the wider ecosystem the fastest? Unless ...
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82 views

Can a fungus become resistant to a chemical such as Potassium Permanganate?

A friend used potassium permanganate solution to treat tinea on the hands/feet but after some initial success, the tinea seems to be making a comeback. Could the fungus develop resistance to potassium ...
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32 views

How host defends against S. pneumoniae capsule?

The host response involves at least phagocytosis and probably localised acute inflammatory response at least after the colonisation. I am thinking how the host can defend against pneumolysin which ...
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58 views

Why PPD test in patients without M.tuberculosis often slightly positive?

I got this question which I interpret as Why PPD test in patients without M. tuberculosis often have slightly positive PPD reaction i.e., a lifelong slightly positive skin test reaction? because ...
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66 views

Why bacteria produce light?

After seeing this video I am curious to know why the free living bacteria produce light. What advantage will they have ? Or is it just an "unintentional" result of one of their pathways ?
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49 views

Can germs develop surfactant resistance in a harmful way?

Germs can develop antimicrobial resistance. It is a problem serious enough to deserve an FAQ page on the WHO website (http://www.who.int/mediacentre/factsheets/fs194/en/). But how about surfactant ...
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159 views

Assay for Beta-galactosidase activity in single cell microscopy

I'd like to be able to measure the activity of $\beta$-galactosidase in living cells with simple optical (maybe fluorescence) microscopy. Ideally I'd like to do a minimum of genetic engineering, and ...
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170 views

At what temperature does DNA re-anneal?

If primers weren't present in PCR at what temperature would DNA re-anneal? I am wondering how primers manage to bind on DNA strands before DNA manages to anneal back together.
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Is iodised salt harmful to the lactofermentation process?

I was discussing sauerkraut recipes with someone on IRC a minute ago, and they warned me not to use iodised salt in the process. My first (and so far, the only successful) batch is one I made with ...
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Why do cell membranes have a lipid bilayer?

Many cells have a cell membrane composed of two layers of lipids, why is it two layers and not just one? What purpose do the membranes serve?
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“Oblong to Allantoids” … Is it valid?

I read on the text book: The characteristic of Dinemasporium are: superficial, cupulate to Discoid conidiomata with brown satae, Phialid conidiogenous cells that give rise to hyaline, oblong to ...
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238 views

What does “cellular” mean in this context?

I came across a confusing word when I was reading a Scientific American story, “Controversial Spewed Iron Experiment Succeeds as Carbon Sink” (by David Biello). It goes like this: “One key to the ...
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1k views

Is there a free alternative to Gelcompar for comparing banding patterns across multiple gels?

In order to run my microbial community samples from my experiments through DGGE, I was required to use multiple gels. Thus it is necessary to compare banding patterns across more than one gel. ...
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24 views

Why can't some organisms match miRNA perfectly to the target mRNA like in plants? [closed]

What causes other organisms to be impaired in making perfect matches like plants do and is there a way to increase matching?
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Clumping factor test

I'm come across this question and I'm somewhat confused: In the test for staphylococci, the clumping factor detects: staphylothrombin DNase mannitol fermentation Fimbriae fibrinogen-binding protein ...
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43 views

Effect of flask position in shaking incubator affects growth kinetics

During some cultivation experiments for my bachelor thesis I noticed that in liquid culture my bacteria (E. coli) grew differently, according to the position in the shaking incubator. Because the ...
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40 views

Alkaline Phosphatase

What is the predominant purpose of Alkaline Phosphatase in skeletal muscle fibers and liver cells. I know that it is a hydrolase enzyme that speeds up the degredation of proteins, lipids, starch and ...