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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Why do flagella form a bundle only when they rotate counterclockwise during chemotaxis?

During Chemotaxis in bacteria with flagella, the flagellar rotation dictates how the cell moves. If the flagella rotate counterclockwise, then they form a bundle at one end of the cell (---O) and ...
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When do plasmids replicate relative to its host cell cycle?

For plasmids is so much shorter than their host cell's genome (about 1/1000 in my case), it will take only 1/1000 time for it to replicate. With respect to cell cycle, when will that replication ...
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Hot water and bacteria

I know that it is common to say, "use hot water when washing your hands" or when you've got a cut, "wash your hands with warm water," etc. I was wondering, why is this the case? Since bacteria grow in ...
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Why are pili more common in Gram negative bacteria than in Gram positive?

Although pili have been observed in some species of Gram positive bacteria, the preliminary research that I have done indicates that pili are significantly more common in Gram negative bacteria. Is ...
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Does freezing microorganisms such as probiotics kill them?

Does freezing microorganisms such as probiotics kill them? If not, what is the process that allows them to "come back to life" after the temperatures are increased? As an example, lets say you ...
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The ring formation of ringworm

I know ringworm is caused by a fungus on the skin, nails or scalp but what causes the rash to form as a ring instead of like a normal spread out rash?
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Non-harmful bacterial invasion of cells

There are bacteria that can enter body cells as parasites. Could it be that some of these are benign, such that the guest will not kill the host cell it lives in (especially in human)?
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Are there single-celled organisms that have evolved from multi-cellular ones?

I'm reading this paper about transmissible cancer cells in clams (Metzger et al. 2015) and I was wondering if there are any single-cellular organisms that are around today that are suspected as having ...
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Microalgae without cell walls?

Most microalgae have rigid cell walls. Dunaliella Salina is a pretty famous example of an algae with no cell wall, but just a plasma membrane. Are there any other microalgae without a cell wall?. I ...
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Regulation of V. cholerae virulence factors

So I know that several different environmental signals, such as pH, bile, and temperature, regulate virulence gene expression in V. cholerae. Specifically, they control expression of the genes ...
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170 views

HIV Rapid Tests

The hiv antigens that are used in the oral rapid tests, are they infectious? The tests do not contain any actual virus but I am curious if the antigens themselves could somehow create the virus on ...
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Reasons for the HIV-1 epidemic

So, the HIV-1 jump to humans occurred as early as the 1920s, but the AIDS epidemic didn't start until the early 1980s. Some things I don't understand about this: Why the delay? What is needed for a ...
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Horizontal Gene Transfer

I understand the different ways bacteria can undergo horizontal gene transfer (transformation, transduction (phages), conjugation (plasmids)). Is there an experimental method to tell how a specific ...
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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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55 views

What is a good source that will help me classify protists?

I am a 15 year old that enjoys looking at the micro world. The only issue that I have is that I can't find a good online source that will help me classify the name of the micro organism that I'm ...
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39 views

Ethanol production by fermentation?

As bacteria are involved in the production of ethanol through fermentation and ethanol is also used as antiseptic that kills bacteria, so how and why bacteria are involved in the synthesis of such ...
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Are there mechanisms that limit the amounts of time conjugation and F-plasmid transfer can happen? If yes, what are they?

Not all bacteria have acquired F-plasmids through conjugation. Some of the mechanisms for this are unsuccesful conjugation events (mechanical disruption), no transfer due to integration in bacterial ...
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57 views

Why don't all bacteria have F-plasmids by now?

Some bacteria can undergo gene transfer by conjugation. Conjugation is a form of horizontal gene transfer, meaning from one (unrelated) bacterium to another (in contrast to vertical gene transfer, ...
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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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111 views

What allows Valonia ventricosa cells to get so big?

Valonia ventricosa are single celled algae that range between one and few centimeters. In rare cases they can reach sizes exceeding 5cm. Weirdly, a lot of the literature covering these organisms ...
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Why are there no known photosynthetic archaea?

I'm taking a microbial physiology course and we noted that, while some archaea are phototrophic, there are no known photosynethetic archaea. Are there any physiological characteristics that make ...
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What happens during kefir fermentation process?

I’ve found many sources about the positive effects of kefir for the digestive system. However I haven’t found any information about the fermenting process. What is the exact biology (chemistry?) ...
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Why is acid alcohol used as a decorizer in the acid fast stain procedure, as opposed to a neutral alcohol?

Is it to neutralize the negative components of the cell membrane, thus preventing the positively charged dye from adhering to the cell membrane?
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To which negatively charged components of the cell envelopes do the crystal violet complexes bind in gram staining?

The gram positive have negative components in the peptidoglycan layer in the form of teichoic acid phosphodiester bonds, and the gram negative have negative components in their outer membrane in the ...
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63 views

Survival of streptococcus after my scarlet fever

I'm currently sick because of scarlet fever but I got treated with antibiotics. I know that after 1.5 day using antibiotics the streptococci I release at home are dangerous anymore. But my question ...
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What is this fuzzy, black fungus that grew on my plates in the 4⁰C room? [closed]

I often find the fungus below growing on my (ostensibly) sterile plates in the 4⁰C room. Presumably it takes a few days to reach this size. The colony looks puffy and dimpled in the middle, like a ...
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34 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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How do Streptococcus thermophilus and Lactobacillus bulgaricus precipitate the curd of swiss cheese?

I learned in my food microbiology class that Streptococcus thermophilus and Lactobacillus bulgaricus precipitate the curd of swiss cheese. However, I was wondering what type of mechanisms do these ...
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Reasons preirradiation of negatively stained and plastic embedded specimens with a low electron dose improve stability to electron irradiation

It is known that preirradiation of negatively stained and plastic embedded specimens with a low electron dose improves their stability to electron irradiation. But my question is why this occurs? ...
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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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123 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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What Websites Have Image Libraries for Bacteria and other Microorganisms

What Websites Have Image Libraries for Bacteria and other Microorganisms? With age of cell phone microscopes and hand held spectrometers it would be interesting and valuable to be able to compare ...
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63 views

How often does bacterial transformation happen?

I have been reading: M. Dröge, A. Pühler, W. Selbitschka, "Horizontal gene transfer among bacteria in terrestrial and aquatic habitats as assessed by microcosm and field studies", Biol. Fertil. ...
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If someone were to die on the moon, would their body decay?

I heard that the footprints of Neil Armstrong are still there, so I was wondering if someone were to die there, would they remain preserved, too? If not how long would it take for them to decay?
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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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Are there any viruses that are part of all land animals?

An article on I Fucking Love Science (linked to below) got me thinking, are there any viruses that have been so successful that they have spread to all land animals similar to Toxoplasmosis which has ...
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Is there any way the food industry can benefit from biofilms?

I realize all of the disadvantages, but I am wondering if the food industry can actually benefit from the formation of biofilms.
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Medium for Pseudomonas?

What is a good minimal medium for Pseudomonas bacteria? Do I need different media for different Pseudomonas species?
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65 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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How many eukaryotes are there on Earth?

I have been reading: William B. Whitman, David C. Coleman, and William J. Wiebe, "Prokaryotes: The unseen majority", Proc. Natl. Acad. Sci. USA 95, pp. 6578–6583, June 1998. [Full Text] [PDF] ...
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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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What are the main principles of the Bacteriological Code?

Although the Bacteriological Code is an important guideline for taxonomists and microbiologists, describing the criteria for delineating species and higher taxa of the prokaryotes, I, and plenty of ...
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How can fresh cavities form at the margins of sliver amalgam fillings on teeth?

Silver amalgam fillings predominantly contain silver a known bactericidal agent and mercury which a known toxin and has bactericidal property. So how is it that the plaque bacteria survive near the ...
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Can an influenza virus carry other infectors with it?

This idea came to my mind when thinking about how many people become ill in many locations with similar symptoms (fever and rough cough) from Influenza. There are of course different types of ...
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49 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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What's the composition of Actinobacteria's hyphae?

I'd like to know which chemical compounds form hyphae in Actinobacteria. Is it the same structure of the cell wall? Thank you
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DNA polymerase I exonuclease activity

Does DNA polymerase I in bacteria use forward or reverse exonuclease activity to remove RNA primers? One of my books says it uses 5' to 3', but another says it uses 3' to 5' exonuclease activity. ...
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Identify the pink mold infecting refrigerated lemons [closed]

I made lemon juice 6 month ago. I just washed the lemon using brush and then cut them into pieces. Then I put one layer of lemon in the bottle followed by one layer of sugar Again one layer of lemon ...
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689 views

Do all Gram negative bacteria cause septic shock?

Do all Gram negative bacteria cause septic shock? If they don't could they if you attacked them with an antibiotic that could lyse the cell? For example any antibiotic that attacks the cell wall, ...