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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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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If a human takes antibiotics are all bacteria in the body killed?

From my basic understanding, antibiotics kill living things, bacteria for example. Do the antibiotics consumed by a human-being distinguish between what they kill? Or do they just kill every bacteria ...
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How to understand influenza strain designations?

What do the strain designations for flu mean? For example avian flu is classified as H5N1, what do the letters H, ...
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How does the microbial environment in your gut initiate?

Clearly, a zygote does not harbor any microbes. As it develops, and the alimentary canal tissue is differentiated, I logically assume that there is still no microbial activity in the fetus's gut. I'm ...
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250 views

Is there any convincing evidence for the existence of nanobacteria?

The existence of nanometer scale microorganisms has been proposed and used explain several phenomena including morphological structures in a martian meteorite (ALH 84001) and implication in the ...
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Are single-celled organisms capable of learning?

I've read that the amoeba is capable of learning. Since these protists have no nervous system, it's safe to assume that even highly simplified learning mechanisms of the Aplysia are miles off in the ...
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Why is there now only one Salmonella species?

Once upon a time, I chanced upon an old microbiology book that detailed the rather colorful world of enterobacteria. Salmonella in particular stood out, as it seemed there were a lot of species: typhi ...
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Do probiotics survive digestion?

Pretty much this. I've been wondering if any of the yogourt and other "health" foods containing living probiotic cultures survive digestion to populate our intestines? If so, is there peer-reviewed ...
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Relationship between our microbiome and personalized nutrition

Recently, it has been asked whether there are 'metabolic types' between humans that can benefit from a sort of personalized nutrition. One answer suggested that one discerning factor could be the ...
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Are there animal models for Clostridium difficile that better replicate human infection than hamsters?

So I'm looking for some information on the infectious dose necessary to colonize a human with Clostridium difficile. There's no human challenge studies, and since it's not a foodborne pathogen, little ...
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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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Why is the microbial ecosystem of the gut so susceptible to disruption by pathogens?

From all accounts, it seems as if the Escherichia, Enterobacter, etc. that live and thrive in the human gut are pretty well entrenched. I know that these microbial populations are often analyzed as ...
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How do baby animals that primarily subsist on cellulose get their initial gut flora?

In the case of mammals like giraffes and koalas, is that bacteria common on the plants they eat so when a baby starts to try to stick something besides its mother's milk in its mouth, it can't digest ...
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Is there an equivalent to “Fields Virology” for Bacteria?

I've gotten a staggering amount of use out of my copy of Fields Virology as a general reference for "getting me up to speed" on whatever pathogen I'm currently looking at. I don't know of a similar ...
11
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Antibacterial hand soaps (and related products); what are they good for?

From Wikipedia: Household use of antibacterials in soaps and other products, although not clearly contributing to resistance, is also discouraged (as not being effective at infection control). ...
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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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What is the advantage of using starter cultures for growing bacteria?

Many DNA isolation and protein expression protocols contain instructions to use a starter culture of E. coli that is then used to inoculate the main culture. What are the advantages of using starter ...
10
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1answer
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Can Naegleria fowleri enter through wounds into the bloodstream?

All the sources I've read said that Naegleria fowleri enters the brain through the nose. But lets say that someone had cuts on their arm or leg and they are swimming in water that is conducive to ...
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135 views

Are these Gram stain substitutions acceptable?

In the context of a Gram stain on a blood smear: Are the following acceptable substitutions and/or what differences could arise by substituting them? Using methylene blue instead of crystal violet ...
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Have there been any positive public health effects due to UV lights?

Occasionally, in hospitals and in eating establishments in the US, they have industrial grade UV lights in sconces attached to the wall (though they seem to be less prominent as the years go by). I ...
9
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48 views

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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What is this microscopic image from Peter Gabriel's New Blood album cover?

This image appears on the cover of Peter Gabriel's album New Blood. It appears to be a photograph of some microscopic biological cell. But it doesn't look like a blood cell to me. What kind of ...
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What's the aim of genetically modifying of foods/organisms?

On news, articles etc. experts talking about Genetically Modified Foods and Organisms often mentions about their disadvantages like, their potential to harm human health allergies may become more ...
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How much weight/volume do microbes occupy within the human body?

Microorganisms constitute the bulk of all the biomass on Earth. I weighed myself yesterday, and wondered how much less I would weigh if I were completely free of bacteria and microbes, inside and out. ...
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Should we be looking for extra-terrestrial life on comets?

I have just read What elements are a possible basis for life? and I find myself wondering whether instead of seeking advanced life-forms at remote locales a La SETI, and perhaps fundamentally ...
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Is it plausible that eukaryotic organelles like flagella and cilia are the result of endosymbiosis with spirochetes?

This was a claim by Lynn Margulis explained over at this link. The sense organs of vertebrates have modified cilia: The rods and cone cells of the eye have cilia, and the balance organ in the ...
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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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How to obtain bacteria samples at home?

As the original question went from hold to closed, I thought I would write up a more appropriate question. How should one go about getting bacterial samples to look at under a microscope at home? ...
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What does the term “relay competent” mean?

I was reading the article of Dallon & Othmer (2010) which deals with cell aggregation in Dictyostelium discoideum. In the introduction of the paper it is said that cells becomes "relay competent". ...
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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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1answer
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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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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] ...
7
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128 views

Any food crops that could grow in a desert provided that they get fertilizer and water

I am working on an idea to provide nearly unlimited amounts of water in desert regions. To make this commercially viable. I would use the water to irrigate desert sand and grow crops. Given my ...
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528 views

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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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 ...
7
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1answer
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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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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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2answers
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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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1answer
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Sugar as a defence against bacteria?

An answer on another SE site mentions that sugar "at a certain level acts as a preservative". I've always been taught that microorganisms eat sugar and expel acids, that is why sugary food are ...
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1answer
79 views

How exactly can dsRNA be introduced to a cell?

Is it just by viruses or are there other means by which it gets into cells, such as plasmid uptake?
6
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1answer
390 views

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 ...
6
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1answer
117 views

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 ...
6
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1answer
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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 ...
6
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1answer
433 views

What is the effect of garlic on intestinal flora?

Now that we can compare whole microbiomes, has there been investigations on the effect of garlic (or diallyl disulfide, its main ingredient) on intestinal flora? From the proven antimicrobial ...
6
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1answer
281 views

Models of quorum sensing for multi-agent systems

Quorum sensing is a system of stimulus and responses correlated to population density that is used by bacteria to coordinate gene-expression. I am looking for a simple computational/mathematical model ...
6
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1answer
524 views

If re-boiling does not curdle the milk, can that be taken as an indicator that the milk hasn't developed the bacteria (and their toxins)?

Usually when left in hot temperature, the milk curdles (which I know when I boil it and it starts separating). If the re boiling does not curdle the milk, can that be taken as an indicator that the ...
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530 views

What happens to lactic acid I eat?

Let's say I drink some Kefir Milk, what happens to the lactic acid in the Kefir Milk that has entered my digestive system?
5
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3answers
153 views

Can genetically modified genes jump to bacteria in the eater's intestine?

The Guardian ran an article a while back talking about GM gene's jumping to bacteria in an eater's intestine. Has other research confirmed this phenomenon?
5
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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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What does the 34/70 in Saccharomyces pastorianus Weihenstephan 34/70 stand for?

I've searched everywhere. No Wikipedia page. No information on NCBI. I searched all occurrences of 34/70 in some primary research articles! The best I've found is this brewery forum where someone ...