Questions tagged [microbiology]
Microbiology is the study of extremely small organisms. This includes organisms like bacteria, fungi, protozoa, and viruses.
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How much thermal energy is released by the anaerobic fermentation by C. Lungdalii grown on hydrogen
For example, reaction H2+CO2 + X --> acetate + biomass.
How much thermal energy is released kJ/g acetate.
Purpose is to calculate the heat balance of reactor.
Thanks!
Dorian
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Why we prevent vaccines from light?
I'm trying to understand why the vaccine is put away from the light. Is it the temperature or is there some other reason?
https://www.health.nsw.gov.au/immunisation/Pages/cold-chain-management.aspx
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Need help identifying this microbe
Sorry for the bad image, we don't have a camera hooked up to our culture room microscope yet. But Has anyone seen these kind of (what I'm assuming are) contaminating bacteria before? We see these from ...
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Conjugation of bacteriophage transduced genes
wonder if it is proven that bacteria can spread genes acquired by transduction or infection with a temperate phage by conjugation or transformation? Can you give me link to article that discuss this ...
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Can you use "colony morphology" for bacterial identification, on the same plate used for initial isolation?
Bacterial isolate: a single species of a bacterium obtained in a pure culture.
Colony morphology: the visual culture characteristics of a bacterial colony on an agar plate.
Observing colony morphology ...
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Is there a difference between adult onset and child onset atopic dermatitis and what is the role of the skin microbiome in the condition?
I am a novice in the field of skin microbiology. I am looking to learn about the skin microbiome and its role in atopic dermatitis. As of right now, based on my readings that the biodiversity of ...
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What are these ciliates doing here during cell division?
A while ago I filmed a short (20 min) time-lapse of the cell division of two ciliates. However, I noticed something odd with their behavior. They appear to push against a piece of debris in order to ...
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How to Resuspend cells at cell density of 8 log CFU/ml of bacterial culture whose CFU/ml i don't know at 600nm, also it doesn't grow well on MRS agar?
According to procedure after 24 hr growth of Lactobacillus delbruckii subsp lactis in MRS broth, I have to resuspend it at 10 raise to power 8 CFU/ml and then inoculate it further. But it doesn't grow ...
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Endospores contact with surfaces
I am currently studying endospores-forming bacteria. To be specific B.subtilis. I noticed that the formed spores have strong contact "grip" with the surface it is forming on. For example, ...
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How can a layperson get their hands on a specific strain that's not readily available commercially?
I'm mostly interested to get my hands on L.plantarum D-103, but there are a few other strains as well. D-103 is e.g. mentioned here https://meridian.allenpress.com/jfp/article/80/10/1682/199965/...
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How to figure out growth/culture conditions for a specific strain?
Specifically, I'd like to find out how to grow ME-3 L.Fermentum (DSM 14241) at home without any fancy equipment.
What food does it need? Sugar? Lactose? Something else? At what temperature does it ...
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What is the easiest way to determine the species of non-tuberculous mycobacteria?
We have isolated a mycobacterium strain from patient sputum using an NTM Elite plate.
When inoculated into an MGIT tube, we observe fluorescence when observed under UV light, which means it is highly ...
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What's the purpose of using more than one culture medium for bacterial isolation?
What's the purpose of using more than culture medium for bacterial isolation?
Why not use just one?
If this is not generally used in isolation of various types of bacteria, I'm concerned especially ...
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what is the main difference of immune response between immune deficiency people and normal people?
The only thing I know about the main difference between immune deficiency and normal people is that for immune deficiency people there will be less adaptive immune response.
Let's take the difference ...
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What are these white, fuzzy dome-shaped contaminants growing on my LB agar plate?
We are attempting to extract bacteriophages from environmental samples. We recently had an issue with an unknown contaminant when trying to grow a lawn of M abscessus for a bacteriophage isolation ...
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Has there been evidence that there has been coevolution in E. Coli strains with the T4 bacteriophage?
According to Evolution of T4-related phages, there have been multiple instances of evolution in the T4 coliphages. Per the article, there are many T-even phages that have insertions from other ...
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Doesn't pasteurization kill gut bacteria such as Akkermansia muciniphila?
I've recently watched two presentations on YouTube (this and this) about Akkermansia municiphila, a commensal bacteria that feeds on the mucus of the gut.
What I find confusing is their claim about ...
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Why does adding calcium chloride aid in bacteriophage infection?
We are attempting to isolate bacteriophages from environmental soil samples and most protocols recommend adding CaCl2 to the media to aid bacteriophage infection, even though they all recommend ...
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Why would it be impossible for gram-positive bacteria to store sulfur as gram-negative sulfur-oxidizing chemolithotrophs can?
I have a question that I am not sure what is the correct answer on <<Brock's Biology of Microorganisms>>
When the book introduces "Cell Inclusions", there was a mini-quiz that ...
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How to judge the distance of nodes in biological evolution tree
I would like to know the method of judging the distance between two nodes in the phylogenetic tree. For example, in the diagram below, is node 299 closer to node 151, or closer to node 201?
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What prevents the diffusion of proton gradient in Gram (+) bacteria [duplicate]
The proton gradient in bacteria is important to power FTPase and flagella. How do Gram (+) bacteria maintain a proton gradient without a periplasm (Gram (-)) or intermembrane space (mitochondria). Why ...
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What are these micrographs of?
There are some images floating around the Internet that were supposedly taken with a microscope, built in the 1920s, that was supposed to achieve resolutions that would normally be ludicrous for an ...
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Does centrifuging and filtering supernatant confer an advantage compared to just filtering?
We are trying to isolate bacteriophages from environmental soil samples. One of the first steps is elution, centrifugation and filtering of the soil samples.
One protocol suggests to:
Elute the soil ...
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How can combusted methane from landfill samples be quantified? [closed]
Background:
For my studies I'm wanting and attempting to make a landfill greenhouse gas emissions (GHG) model that predicts the amount of greenhouse gas equivalent emissions ($GHG_{eq}$ [tonnes/year]) ...
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Is it safe to autoclave waste at the same time as lab equipment?
We have recently moved into a lab space where we share an autoclave with other people.
We generally autoclave empty beakers, flasks, etc., before running experiments, and we autoclave waste (Petri ...
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What concentration of carbenicillin will inhibit Pseudomonas in 7H9 broth?
As I described in a previous question we are trying to grow M. Smegmatis in 7H9
broth. We added 20ug of carbenicillin to 20ml of broth, but it still got contaminated with what is likely Pseudomonas.
...
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What is this small creature on the bottom of this leaf?
This first one appears to have been flattened by the slide cover.
This one is not flattened.
Probably like .2/.3 mm in size. All of them seem dead because they are doing nothing. All on the underside ...
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What microbial contaminant grows blue on L-agar/L-broth and is resistant to carbenicillin?
We are trying to grow liquid cultures of Mycobacterium smegmatis as a host for bacteriophages, but we have been having issues with contamination. Our latest attempt went like this:
Tuesday 1 pm: ...
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Could abiogenesis still be ocurring? [duplicate]
From my understanding, most biologists believe that under certain conditions life can form from inert chemicals. If the conditions for this to happen still apply, is it possible that in bodies of ...
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What kind of filter can be used to filter sterilize ADC?
I am using this recipe to mix my own ADC (Albumine+Dextrose+Catalase), without the catalase for a microbiology application.
It says use a filtering apparatus to sterilize the ADC because it can not be ...
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How does the cell-wall ultrastructure of gram negative bacteria justify it being unable to Sporulate?
The following is a quote from my Microbiology Lecture PPT: "Some gram positive bacteria but NEVER gram negative ones produce spores under harsh conditions".
It got me wondering why gram ...
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How bacteria respond to toxic viral proteins?
The lysis-lysogeny state of bacteriophage lambda is well known. Under certain conditions, the phage will enter the lysogenic state after infection of a bacterium. Then, after a while, the phage ...
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Is there a way to relate the OD to cells/mL without doing a standard growth curve?
I am helping out with an experiment with multiple bacterial cultures (>20 species). I need to a very specific concentration (cells/mL or CFUs*/mL) for this purpose. Unfortunately it appears that ...
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Understanding the names of microorganisms of the normal body flora
I'm taking an introductory course to microbiology and immunology, and i have been required to memorise the following microorganisms of the normal flora.
I'm trying to understand before I memorise, and ...
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My boyfriend and I found this Object on the beach wondering if anyone could help
My boyfriend and I found this object on the beach and need help Identifying it. It looks like a Shark Tooth not for sure. Found in Gulfshore Alabama on the beach. It looked rusty when we found it but ...
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Why does low redox potential mean less oxygen?
I often see statements about adding reducing agents like cysteine to anaerobic medium to decrease the amount of the dissolved oxygen.
However, I am not sure why.
I am wondering if it is because under ...
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Determine acidification of milk (no-probe/contact/destruction)
For a project, I am trying to figure out if it is possible to determine the acidification of milk without probing, touching, destroying or opening the sample, thus leaving the sample inside the ...
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How would you measure the diameter/radius of a non-circular bacterial zone of inhibition?
Typically when we're testing the antimicrobial effects of some substance on bacteria growing on an agar plate, we get the area or diameter/radius of the zone of inhibition. But what do we do in cases ...
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Setup of terrarium for an early life experiment
I'm building a terrarium in which an early life environment will be simulated. Over multiple years a few experiments with different starting molecules/atoms will be held in it. The selected materials ...
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What's the term for "Amino acid regulating the expression of components used to synthesize it"?
In the tryptophan operon wikipedia page, it says under the Attenuation title:
A similar attenuation mechanism regulates the synthesis of histidine, phenylalanine and threonine.
If my reading is ...
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Does ellagic acid dissolved in DMSO react with Brain Heart Infusion media?
I dissolved 2mg of Ellagic acid in 500 microliter of DMSO. I used 100 microliters of this solution to test for antimicrobial susceptibility against E.faecalis by adding it to 100 microliters of BHI ...
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What nutrients are necessary for Bacillus subtilis germination?
What are the necessary conditions to germinate Bacillus subtilis spores? Under laboratory conditions, spores of B. subtilis are often heat-activated for 30 min at 70°C to increase their germination ...
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Can organisms grow on acetic acid?
Can organisms grow on acetic acid and water (with <1%, all inorganic, impurities), i.e. using acetic acid as a carbon / energy source?
If so which concentration of water would it start at? (...
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What is mechanism of action of ellagic acid as an antimicrobial compound?
Ellagic acid (a polyphenol) works as an antimicrobial compound. But what is its mechanism of action?
I found these 2 research papers related to this, however the mechanism of action is not clearly ...
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Does centrifuging the bacteria culture removes bacteria leftovers?
Usually, we centrifuge bacteria culture to either replace the media, control its density (OD), ..etc. I know that when centrifuging the cells are pushed to the bottom while the media (solution) ...
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Is bacterial respiration a continuous process?
Respiration in micro-organisms is the process of releasing energy from food. There are two ways of doing so: Aerobic respiration occurs in the presence of oxygen and produces ATP from the complete ...
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Can disk diffuson be used, without diluting a broth culture to match a 0.5 McFarland turbidity standard?
In this video, there doesn't seem to be a process of diluting the broth. I'm not looking for extremely accurate test results, all I need is to see if a particular colony is susceptible to the ...
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Can features of modified plasmids be divided into prokaryotic features and eukaryotic features?
Here's what I understand and please correct me if I am wrong:
Plasmids modified for gene therapy or genetic engineering should contain factors for certain functions in prokaryotic cells. For example, ...
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can a mutualistic or at least symbiotic relationship between two organisms or more be artificially induced by human means?
I was wondering about such a question because I thought about the possibility of using microorganism to regulate the atmosphere and Each species may be suitable for different environments and purposes....
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Can the Monkeypox virus be spread by mosquitoes?
I am wondering if the Monkeypox virus could be spread by mosquitoes since it is part of the Smallpox family.
While doing some online research on this possibility, I came across this abstract taken ...
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