Proteobacteria: The 16 Major Groups Examined

proteobacterium enterobacteriaceae

Proteobacteria Proteobacteria is the second largest group of bacteria. This phylum contains 1,534 species – or 32.3% of all known bacteria. Proteobacteria are all gram negative, but otherwise represent a diverse range of organisms such as the Purple Phototrophic, Nitrifying bacteria and Enteric bacteria – as well as the bacteria responsible for animal bioluminescence. Here … Read more

Firmicutes: The Single Largest Group Of Bacteria

firmicutes bacteria are rod shaped

Firmicutes Firmicutes are the single largest grouping of bacteria. Though because it is dominated by a number of very successful genera, it contains somewhat less diversity than the proteobacteria. Of approximately 2,475 species in 255 genera, 40% of these species are aggregated in just 6 genera: Lactobacillus (100 species) Mycoplasma (110 species) Bacillus (114 species) … Read more

The Euryarchaeota: Nature’s Lovers of Salt

crenarchaeota in salt lake

Euryarchaeota The Euryarchaeota are a diverse group of organisms that live in extremely saline or salty environments. I.e., originally salt lakes, but now also on the surfaces of highly salted foods such as fish and meats. These organisms are called extreme halophiles. This description means not only that they can live in highly saline environments, … Read more

The Crenarchaeota: Lovers of Extreme Temperatures

hot spring rife with Crenarchaeota

Crenarchaeota The Crenarchaeota are a smaller group than the Euryarchaeota which contains the majority of the known Archaea. Crenarchaeota are primarily found in extreme environments, either hot ones or cold ones. Little is known about the cold adapted species, except that they live in considerable numbers – 104 per ml. They are found in the … Read more

Bacteria Classification: 16 Phyla Ordered by Species & Genera

bacterial classification by gram staining

Bacterial Classification The taxonomy of bacteria is not very definitively worked out yet. Especially the higher levels of classification. Some authorities believe that the degree of variance between different bacterial groups is sufficient to give them each ‘Kingdom Status’ of their own. Thus in the 9th edition of “Brock: Biology of Microorganism” you will find … Read more

Bacteria: Shapes & Sizes Of These Unseen Miracles of Life

shape of bacteria cocci

The Shapes, Sizes, Fimbriae and Endospores Of Bacteria Bacteria are microscopic, single-celled creatures which live mostly on the surfaces of objects – where they grow as colonies. Bacteria are very important. Both to the world as a whole and to mankind in particular. Bacteria are important in making soil, feeding cows, controlling insects, making medicines, … Read more

Archaea: 27 Characteristics Of These Most Ancient Organisms

archaea vs bacteria in microbial mat

Archaea vs Bacteria – Characteristics Compared Archaea are microscopic, single-celled organisms. Though ancient creatures, they are a relatively recent discovery. Modern science only learned about them in 1977, when they were discovered by Carl Woese and George Fox. The Archaea are a diverse and fascinating group of micro-organisms and the Korarchaeota (one of the group’s … Read more

How Many Species Are There? The truth laid bare.

how many species are there in the world

So just how many species are there exactly? This is a question for which many modern biologists would like a definitive answer. But for which there are only many less-than-definitive answers. I am constantly running into the problem of how many species I should say there are in this group, or that group of organisms. … Read more