Questions tagged [bacteriology]

A subdivision of microbiology dedicated to the study of bacteria.

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What would cause E. coli to change from filamentous growth to normal growth?

In my lab we've observed a phenomenon in which a culture of E. coli is found to shift from normal rod growth to filamentous growth and then back to normal rod growth again several times over the ...
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Why don't bacterial cell walls prevent bursting when attacked by the complement?

The complement system creates pores in cell membrane which leads to influx of lots of water thereby causing lysis of bacterial cell. But what I fail to understand is that if bacteria have cell walls ...
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How can E. coli proliferate so rapidly?

The E. coli has a genome with approximately 5×106 bp. The main DNA polymerase involved in its chromosome duplication (DNA pol III , the one with highest processivity) can polymerize ~103 nucleotides ...
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Why do bacteria produce H₂O₂?

I recently read up that people with NADPH oxidase deficiency (Chronic granulomatous disease CGD) have a tendency to be infected by Catalase positive organisms. NADPH oxidase helps produce the $H_2O_2$ ...
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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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How and when did sex evolve?

As I know evolution comes bit by bit mutation by mutation How sex evolved which requires a major change in at least two individuals one to become male and one to become female ? When that happened ...
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Aren't antibiotic resistant probiotics dangerous?

Multidrug resistant probiotics are often recommended by doctors in various cases. But since bacteriae can easily exchange genes by conjugation or other means they could promote the drug resistance of ...
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Would current-day human-initiated panspermia be effective?

With current technology, we are able to easily send a probe to the Alpha Centauri star system at a speed of about 20 km/s (velocity of voyager probe), which means it would take about 65000 years to ...
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How is the exogenous DNA protected from degradation during bacterial transformation?

During transformation, a bacterium can take up DNA from its environment. A small fraction of bacterial species are known to be naturally competent, meaning that they can engage in this sort of ...
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Is this a bacterial colony?

On the physics StackExchange site people are trying to figure how and why these branching structures formed. The two questions can be found here and here. The latter had no cooling fans and was ...
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How do infectious bacteria determine when their numbers are high enough to attack a host?

When you get sick, you generally don't contract enough bacteria at once for them to succeed in battling your immune system, right? Their numbers must gradually increase in the host's body before they ...
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Why do different bacteria have different shapes?

Why do different bacteria have different shapes? Is it only related to their function?
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How to measure bacterial content

I´m using water container placed on a radiator to humidify room air. Someone might argue that it is a perfect nest for bacteria. I have to put copper coins into the water to kill the bacteria. I ...
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Does soap kill human cells?

I see many products, particularly hand soap and cleaning products, that claim to kill 99.9% or more of bacteria. This makes me wonder, if the chemicals are potent enough to break down bacterial cell ...
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Why does botulinum toxin seem to be more dangerous to humans than to other mammals?

Various mammals seem to get away with eating parts of carcasses that we would prefer to not even touch, and that we assume will make us sick. Because of that, I assume botulinum toxin is more ...
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How much of the weight of yoghurt is due to bacteria?

I recently started making all kinds of bacteria-processed foods by myself (such as yoghurt, but also Sauerteig and so on), and I found myself wondering how much of the weight of these products is ...
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Why do gram-negative bacteria attack the digestive system more than gram-positive ones?

I was researching for a biology project on the subject of contagious infections of the digestive system (mainly the intestines) and almost all of the bacteria that came up (E.coli, Shigella, Cholera, ...
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Alternatives to CFU plating for measuring number of viable cells?

I am hoping to measure growth rates of a bacterial culture in several growth conditions. I am concerned that these growth conditions may cause cell death, which would lead to a decreased ...
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Bacterial cell lysis - what solution to use?

I am trying to determine how quickly detergents act on bacterial cells (cell lysis). I would like to compare some detergents at difference concentrations for bacteriolytic activity. I don’t care about ...
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125 views

Which is the most extreme thermophilic bacteria known?

Extreme thermophilic bacteria thrive at any temperature above 40/50°C. Thermotoga Maritima seems to be the bacteria that can survive at the highest temperature up to 90°C (reference 1, table 2). I ...
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Is there a detectable amount of bacterial DNA in the blood of infected persons?

With which bacterial infection in humans has it been shown that bacterial DNA can be found in the blood? If any is found it is likely not to be very much, and even difficult to distinguish from ...
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Can Helicobacter pylori be eradicated naturally?

This question is not to discuss whether substances that have anti-H. pylori activity work or not, or to discuss the pros and cons of such but from a medical perspective. Assuming that one is able to ...
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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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Pink growth (aka pink slime) in bathtub or shower

I was wondering if anybody had studied or was knowledgeable about the pink growth that people often find around water fixtures in their homes, especially bath tubs and showers? My understanding is ...
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Can general soap kill bacteria?

I have read that general soap can kill bacteria by opening holes in the bacterial membrane. http://questions.sci-toys.com/node/90 However, I found some articles as well saying that it cannot. http:/...
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Can an argument be made that humans are 90% bacterial?

On the blog, All about Scientist in Microword: Microbiology, I read the post We are 90% bacteria, actually, which says that humans are 90% bacterial cells. If this is the case, then why don't we ...
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Bacteria trapped in crystal inclusions found 'alive' after 50,000 years - what were they eating all that time?

The phys.org article Biologists find weird cave life that may be 50,000 years old describes the announcement by NASA Astrobiology Institute director Penelope Boston at the 2017 AAAS meeting$^{(1)}$ of ...
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Why do some bacteria have most genes on the leading strand of the genome?

Genes in the (+) strand are black and genes in the (-)strand are red. The gene distribution in E. coli genome is somewhat expected: transcribed regions would tend to alternate with non transcribed ...
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Can Hepatitis be caused by Bacteria?

There are many information about viral hepatitis. But it is interesting for me, can bacteria cause the hepatitis too?
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How do I measure bacterial growth in agar dishes (either by cell mass or by cell count)?

I am doing an experiment in which I am growing S. mutans in agar dishes, and I am not sure how I would measure the growth of the S. mutans. I am also not sure if I would do this by measuring cell mass ...
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Does every wave length of UV kill bacteria?

Will every wave length of UV work for killing bacteria? So will UV A, UV B and UV C all work? Or will only the shortest of the three, UV C, work? Also, will the average UV lamp help against bacterial ...
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How does heat shock transformation work?

What exactly happens when competent cells like DH5ɑ are heatshocked with DNA present? How does the DNA get inside the cells? Specifically, why are all the steps necessary? What if you heatshock right ...
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Do free computer programs exist that can simulate drug permeability in bacterial membranes?

I am currently trying to make derivatives of a molecule in hopes of making it more permeable to bacterial membranes. I wanted to know whether there are any bacterial membrane simulating programs where ...
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How can promoter binding sites be determined?

I have been trying to find out which sigma factor is responsible for the transcription of RNA polymerase subunits $\alpha$ (rpoA) and $\beta ^{\prime}$ (rpoC) in Bacillus subtilis. I would expect it ...
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433 views

Whole genome amino acid composition tool?

I'm interested in a statistical tool to get bacterial codon usage at genomic level. Ideally, the tool should be flexible to analyse hundreds of bacterial genomes. I've looked in MeSH terms database ...
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Can bacteria, viruses, and cancer cells be destroyed by resonance?

Radiotherapy has been used to treat cancer. Can the resonances by coordinated electromagnetic waves (and/or other forms of waves), of various frequencies, amplitudes and pulse rates, directed from ...
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What is the advantage of using plant-derived antibacterials rather than bacteria-derived antibacterials?

So obviously we have a big problem with antibiotic resistance. Most of our antibiotics originate from bacteria themselves (or are synthetic variations on scaffolds which originate from bacteria). I ...
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1answer
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Proteins that are strongly overproduced in E. coli and S. cerevisiae?

I'm looking for some pointers to proteins that produce at really gigantic levels in E. coli and yeast (S. cerevisiae). Can anyone point to some champion proteins? Even in inclusion bodies and non ...
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Mutation-immunity in Luria-Delbruck experiment

If experiments like those of Luria and Delbruck on E. coli and T1 phage are the main source of our confidence in the mutation-immunity model, is it then highly unlikely that there are other types of ...
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167 views

What sort of biofiltration is best for a small, portable, biofiltration unit?

I've been exploring the idea of a system to allow re-use (drinking) of RV greywater, or at least the freedom to dump in storm drains (I think the requirements are looser about this, but it still has ...
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Conjugation in bacteria

I was studying about conjugation in bacteria, I have a doubt. In conjugation F- cell transforms into F+ cell when there is a formation of sex pilli in between the two. The doubt is if the F- cells ...
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Is 1 g/l living biomass for a Biogas fermenter plausible?

A usual number for a healthy biogas fermenter is $10^9 - 10^{10}/mL$ Bacteria, 10-15% of which would be methanogenic archae. Exceptionally healthy fermenters have more total bacteria and up 25% archae....
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How dirty are bugs? And is it okay if they touch food?

Sometimes I see people throw out an entire drink or bowl of food because a small bug was in it. Are they justified in doing this? Is there enough bacteria on common species of bugs (like ants, flies, ...
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Approximately how long do bacteria live for? [closed]

I would like to know how many days or years do the bacteria live approximately.
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What is the advantage of restriction enzymes cutting only at specific sites?

Bacteriophages have sequences which often do not have specific sites for restriction enzymes of bacteria to cut at and so can attack the bacteria. Wouldn't it be better if bacteria had something "...
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How to identify genes required for biofilm formation

This is just a homework question: Q: Let’s assume that there is an unknown set of E. coli genes that are required for biofilm formation. Describe a genetic experiment you could perform to try to ...
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Gas from bacteria that's not methane

Is gas produced by bacteria always mainly methane? Or, are there bacteria out there that produce some biogas composed mainly of hydrogen, natural gas, propane, butane?
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Can I kill bacteria with distilled water?

Given that bacteria are hypertonic (contain more salts) compared to distilled water, and that they rely on ion concentration differences across the plasma membrane to survive, can I kill a bacterial ...
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685 views

Does antibacterial soap work chemically?

Normal soap requires scrubbing, does anti-bacterial soap require scrubbing too? Since it (I assume) works chemically, can I produce the same cleansing effect without lathering with soap and using anti-...
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Why are bacteria and archaea in different domains?

As I understand it, the main difference between the Bacteria and the Eucaryota domains are that eukaryotes have a nucleus and bacteria don't. I understand that bacteria and archaebacteria have enough ...

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