In nature, a stunning variety of bacteria, (micro)algae, fungi and other tiny folk can be found. Most microbes are unicellular and small enough that they require artificial magnification to be seen. The video gives an artistic impression of the broad spectrum of shapes which, invisible to the naked eye, are present amongst us. Interestingly, some of these microorganisms are able to transform dyes. You could use them individually, or combine them for a better effect. There are two pathways for treating the dyes: total breakdown of the dyes (biodegradation) and conversion of the dye into other products (biotransformation)

 
 

Microalgae

 
Petri dishes with algae cultures. Credit: Solazyme

Petri dishes with algae cultures. Credit: Solazyme

 
 

Algae (singular: alga) are plant-like protists that can be either unicellular or multicellular. Some kinds of algae can decolourise the more common textile dyes. Although the high concentration of salt in the waste water stream is commonly lethal to algae, a species of algae which can decolourise under salty conditions does exist. There are two ways by which algae can deal with dyes. The first one is adsorption of the dye and the second method is using the dyes as food for their growth. The rate of decolourization by algae depends on the chemical structure of the dyes and the species of algae being used. Algae can also produce oxygen, which makes further degradation of the dyes by other microbes easier.

 
 
 

Bacteria

 
 
Bacteria inspired artwork. By Rebecca Potash '16, "Tribal Warfare," lithography and screen print.

Bacteria inspired artwork. By Rebecca Potash '16, "Tribal Warfare," lithography and screen print.

 
 


Bacteria are found in nearly every habitat on earth, reaching from the depths of the ocean to the skin and intestinal tracts of humans. Most bacteria are harmless or helpful, although bacteria are usually noticed when we get ill from them. Bacteria are prokaryotic, which means they do not have a true cell nucleus: their genetic material (DNA) usually floats around in the cytoplasm. Bacterial families can be organised in different ways. A often used way to organise them is per shape. Common shapes include spherical (coccus), rod-shaped (bacillus), elongated (filamentous) or curved (spirillum, spirochete, or vibrio). All bacteria contain a cell wall made out of peptidoglycan. This wall protects them from the outside world but still allows for motility and communication possibilities between different bacteria, or with its environment.

 
 
 
 

Fungi

 
Mushroom Spores. Made by Ernst Haeckel (1904)

Mushroom Spores. Made by Ernst Haeckel (1904)

 
 

Fungi are eukaryotes, meaning they have a cell nucleus containing their DNA. Some multicellular fungi, such as mushrooms, resemble plants, but they are actually quite different and are more closely related to animals. Fungi are not photosynthetic, and their cell walls are usually made out of chitin rather than cellulose. Unicellular fungi, yeasts, are included within the study of microbiology. There are more than 1000 known species and yeasts were probably the first organisms to be domesticated. Yeasts are found in many different environments, including soil, water, plants, animals, and insects. Some yeasts have beneficial uses, such as causing bread to rise and beverages to ferment; but yeasts can also cause food to spoil. Some even cause diseases, such as vaginal yeast infections and oral thrush.