What would the earth be like if there are no bacteria to decompose animal and plant remains?

Updated Feb 6, 2018

Those are called saprophytes, although there is a wide range, and some fungi also perform this function.

If no decomposition was happening at all, then the nutrients wouldn’t be available for recycling into plants, so my guess is that all other life on earth would eventually starve. It might take awhile.

Also, partly decayed plant and animal matter is among the things consumed by worms, insects, etc, so it would disrupt the food-chain / food-web from that angle, as well.

Edited To Add: Another group of bacteria whose absence would be disastrous are the participants in the nitrogen cycle, because all plants need nitrogen in a form that is generated by those bacteria.

Edited To Add Again: I recall reading an article stating that, plant matter (fallen leaves, etc) near the Chernobyl nuclear disaster site wasn’t breaking down as normal. If true, that suggests that, the radiation has harmed a range of saprophyte bacteria and fungi. This could have a sort of secondary impact on the ecosystems there, for future plants and animals.

Where would you settle down if you were the only human on the planet?

Updated Feb 6, 2018

That depends on what resources were available.

For example, if the world were just like it is now, but everybody else disappeared, I would live in a large city, so that I could salvage old buildings, food, fuel, vehicles, medical supplies, etc. Like Will Smith in, “I Am Legend”. But preferably without the zombies.

The place would need a reasonable climate; not too hot or cold. You would need to be able to grow food all year round, with leafy greens, broccoli, etc, going through the winter.

You don’t want to freeze to death, but you also don’t want to be in a tropical area with disease-carrying insects (e.g. mosquitoes with malaria).

You would need a reliable source of fresh water; either some kind of spring, or regular rain that you could collect in tanks as it drains off the roof of your house.

Reliable fishing would help, so you should be near the ocean, or a large lake. Perhaps someplace where you could use nets for crabs.

A decent climate would help you to keep some animals, like chickens, or a couple of cows that you could milk.

There are plenty of cows and sheep in my area, so I could stay fed for an extended period. This would be less available in some more urban areas. In some places, you would have to actively go hunting. Again, this is a climate issue.

If you could get some solar electric panels, they work best in middle latitudes.

Time-frame and transportation would be a factor. For example, I have zero clue about how to fly an airplane, or sail a boat, so, if it happened tomorrow, I would be confined to the island where I am now. In that case, I might head to a larger city, even if I had to walk for several weeks.

If all the cities and human-built infrastructure also disappeared, it would be much more difficult, but you could still survive with the right climate and food/water situation.

Could chemicals be used to mutate strains of bacteria and/or fungus and/or viruses?

Answered Dec 13, 2017

Sure, you can use certain chemicals to cause genetic mutations.

The catch is that, the mutations will be totally random, and you cannot direct it to any particular part of the genome.

You could randomly disable important genes, by causing a SNP or a frameshift error, and kill the microbe.

The keyword is, “random”.

Why do hand soaps say they clean 99.9% of bacteria and not 100% or 95.6% for instance?

Answered Dec 12, 2017

All of that is advertising hype. Don’t worry about any of it. Just use the cheapest regular soap that you can get at your local supermarket.

The whole “antibacterial” claim is rubbish.

From a microbiologist perspective, these “antibacterial” products are a bad thing. (long, scientific story).

Just buy whatever soap is the cheapest, and which your skin feels OK about.

What is the best textbook on medical microbiology?

Answered Dec 12, 2017

I have used Medical Microbiology by Murray, et. al.

With these textbook recommendation concerns, I suggest going to your university library, and looking at what they have on the shelf (or in the library catalogue). Especially see if they have multiple copies of a certain book. That will often be the one that your lecturers/professors are working with.

Who is the father of microbiology?

Answered Dec 12, 2017

Here’s another vote for:

Antonie Philips van Leeuwenhoek

He was an old-style scientist, who had a day-job, and just studied things because he was curious. If I am ever visiting an area where his original microscopes are on display, I will make a priority to check it out.

Other milestone-type people:

John Snow, who identified a public water pump in London as the source of a cholera outbreak, in 1854.

Robert Koch.

Louis Pasteur.

Alexander Fleming.

Does microbiology include chemistry?

Answered Dec 12, 2017

Don’t worry too much, but, yes, you need to take some chemistry.

After all, microbes (and people) are basically bags of chemicals getting into structures, and having some reactions.

Everything is made out of chemicals.

You don’t need to know anywhere near as much as someone who is actually majoring in chemistry.

I took significantly more chemistry and biochemistry than was required, and still survived (just barely in couple of cases).

What is the future of microbiology?

Answered Dec 12, 2017

Continued work on drug discovery in the long-standing “arms race” with antibiotic resistant bacteria. This is the potentially the largest public health issue in modern history, and in the coming decades. A related concern is finding more ways to get drugs into Gram-negative species.

The worst-case scenario is (no-joke, no-exaggeration) a replay of the medieval plagues, when more then half the population of Europe died. There is actually a real risk that humanity could be brought to its collective knees again. We could be exterminated within a few hundred years. But don’t worry – the microbes will continue to thrive just nicely, on their planet.

CRISPR / Cas9 originated as an immune system that bacteria use to defend themselves from bacteriophages, but may be a viable tool for gene-editing in humans. This has the potential for major ethical and legal implications. Do you have enough money to buy a better genome (for you or your child)?

Phage therapy to treat infections. Lots of technical problems, and not likely for prophylactic use.

Microbiomes, for humans and also other animals. Right across the road from me, people are working on trying to get cows to stop belching so much methane (which is generated by microbes in the cows’ gut).

Pharming, which is using microbes to produce drugs. This is where antibiotics were originally discovered (although that was by accident). Synthetic insulin is already manufactured using microbes, and there will be more drugs in the future, including both peptides and small molecules.

Bioremediation, for things like oil spills. Also, there are microbes that are able to eat a certain kind of plastic.

Plant diseases. This has very large economic implications for agriculture, and human implications involving famines.

Synthetic biology. Some of this is cool, like, “what is the simplest organism that we can make, and it will still be able to survive?” However, there are issues involving efforts to legally patent life forms, along with other ethical and economic risks.

If life is ever found on another planet or moon, it will be a microbe.

Biological weapons. Unfortunately, science isn’t always nice or helpful.

What are the best books on microbiology?

Answered Dec 12, 2017

I’ll add another vote for:

Brock Biology of Microorganisms by Madigan and Martinko

It’s a very good general textbook, and is usually the first place I look for a basic overview of something. I used it all the way through university undergrad.

Other related recommendations:

Biology by Campbell (a different one, not me!)

Biochemistry by Voet and Voet

Chemistry by Blackman

Chemistry by Silberberg

Immunology by Kuby

Medical Microbiology by Murray

Molecular Biology by Weaver

Molecular Cell Biology by Lodish