Microorganisms is a scientific, peer-reviewed, open access journal of microbiology, published monthly online by MDPI.

A microorganism, or microbe, [a] is an organism of microscopic size, which may exist in its single-celled form or as a colony of cells. The possible existence of unseen microbial life was suspected from …

Dec 4, 2025 · The major groups of microorganisms—namely bacteria, archaea, fungi (yeasts and molds), algae, protozoa, and viruses—are summarized below. Links to the more detailed articles on …

Apr 5, 2022 · Microbes are tiny living things that are found all around us. Also known as microorganisms, they are too small to be seen by the naked eye. They live in water, soil, and in the air. The human …

Aug 4, 2025 · Microorganisms—organisms too small to be seen with the naked eye—pervade every corner of the planet. They flourish in soil, water, air, and even the most extreme environments …

Microbes, which are also called micro-organisms, are a group of organisms that are too small to be seen with the naked eye. Despite being even smaller than the human cell, microbes still vary dramatically …

Microorganisms are the earliest life forms on earth, which originated 3.5 billion years ago. Microorganisms refer to tiny and invisible organisms, mainly including fungi, bacteria, viruses, …

Apr 29, 2017 · A microorganism is a living thing that is too small to be seen with the naked eye. Examples of microorganisms include bacteria, archaea, algae, protozoa, and microscopic animals …

Microorganisms differ from each other not only in size, but also in structure, habitat, metabolism, and many other characteristics. While we typically think of microorganisms as being unicellular, there are …

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