Aaliyah Faried
Its not just PRETTY, it is POWERFUL!
We, aspiring microbiologists , have most definitely worked with Micrococcus before but do we know that the natural pigment produced by this bacteria have so many properties that is beneficial to us. Well lets find out …
Bacterial pathogens produce pigments which may be used to increase their virulence. These pigments can be useful in our daily lives, thus, POWERFUL IN PINK. The bacterial specie that I have chosen is Micrococcus roseus , the rosy-pink pigmentation had captured by sight, but the profusion off information made me realise that these bacterial pigments are not just about their looks. They have way more to them. The pigment produced serves many constitutional purposes, such as protection from UV light and oxidative stress as well as plays a role in absorption of light in plants.
In Microbiology we have learnt that we have good bacteria and bad bacteria. Micrococci are not always pathogenic. We NEED them! As they normal inhabitants of our bodies and are essential for maintaining a balance in the microbial flora of skin. M.rosues is a gram-positive aerobic bacteria that is often seen growing in tetrad arrangements.
Micrococcus roseus is a gram positive bacterial cell that grows in the tetrad arrangement. The normal habitat for this Micrococcus species is skin, soil, and water. It derives its name from the carotenoid pigment that it secretes. Isolated colonies on a TSA plate are circular, 1.0–1.5 mm in size, slightly convex, smooth, and pink in color. Optimal growth temperatures range from 25 to 35 degrees Celsius. Micrococcus roseus is a strictly aerobic organism.
Micrococcus roseus red colony on blood agar Nutrient agar #Micrococcus #roseus #RedPIGMENT
Lets backtrack a bit. I have told you about the bacterial specie I have chosen but I have not told you about the history behind it.
This bacterium derives its name from the carotenoid pigment that it produces. The word "roseus" originates from Latin meaning rosy or pink, this is clearly shown by the pigmentation produced by this bacterium. ‘’Micrococcus’’ as we know is a genus of bacteria in Micrococcaceae family which are found in various environments: In soil – M.denitrificans, In marine waters – M.colpogenes, In skin or skin glands – M.flavus, In milk (I’m sure we all have heard about this) – M.luteus and In air – M.roseus.
What do bacterial produce ? natural pigments
What do these natural pigments contain ? Many, Many properties that are essential to us.
Many researches focus their attention on the natural pigments produced by bacterial species. The biological properties present in these pigments include antimicrobial activities, antioxidant activities, anticancer activities and anti-inflammatory activities. By using these natural pigments, we can avoid using synthetic or alternative drugs, as we require that nature additives and traditional medicines that are present in food due to these microorganisms. These natural products can be used economically and pharmaceutically. It adds an economic value to food additives, cosmetic drugs and personal care products And is potentially used as a pharmaceutical application.
I said POWERFUL IN PINK but there is yellow.
Carotenoids are fat-soluble pigments that give colour to plant parts and these colours can range between yellows, oranges and reds. Thus the yellow. Carotenoids is one of the most important pigments which belong to the chemical group isoprenoid polyenes. this group produces a pigment that is lipid-soluble and yellow-orange-red in colour.
Carotenoids mainly act as a photochemical buffer, allowing for the protection of both photosynthesis and the photodynamic killing of chemosynthetic organisms. However in M.roseus carotenoids are not present to protect the cells from photodynamic killing.
According to research and studies it is shown that these pigments are closely linked to photosynthetic membranes, as these membranes aid in the harvesting and transfer of light energy to chlorophyll, and in the protection of photosynthetic network against photooxidation. These pigments are present in a wide variety of photosynthetic bacterium as they partake as an important taxonomic marker for identifying a species from a genus. The major pigment of a M.roseus strain is known as Canthaxanthin. M.roseus pigments mainly contain α or β carotene derivatives with the main pigment canthaxanthin.
The article above informs us more about test performed on a M.roseus strain. These studies have indicated that carotenoids present in M.roseus does not protect the bacterium against photodynamic killing. Studies prior to this had been conducted on the isolation and characterization of carotenoid pigments from a mesophilic M. roseus strain, results had indicated the presence of around nine pigments. From these nine pigments six had been identified as: (phoenicoxanthin) 3-hydroxy-4,4'-diketo-3carotene, dihydroxy-3,4-dehydro-a-carotene, dihydroxy-ax-carotene, diketo-a-carotene, polyhydroxya-carotene and like I have mentioned earlier – the major pigment – (canthaxanthin) 4,4'-diketo-,-carotene.
The screenshot above had been taken from the article : https://jb.asm.org/content/jb/96/1/234.full.pdf
In the above tree diagram, all the pigments that were studied, were isolated as mixtures of cis and trans isomers.
The results that had been obtained, some of which were :
Pigment I had been characterized as a mixture of cis-trans isomers of a dihydroxy-3,4, dehydro-a-carotene which was isolated as a diester.
Pigments IV and VI were isolated in minute amounts and the only data that had been obtained was on chromatographic behaviour.
Pigment V presented a smooth and symmetrical absorption spectrum. Saponification of the reduction product did not change the pigment's polarity, this was shown as two hydroxyls were not present.
The absorption spectrum of pigment VII was similar in shape to that of pigment I. Saponification greatly increased the polarity of this pigment as the product contained two hydroxyl groups and the second functional group was an ester
Pigment VIII had a symmetrical spectrum suggesting that both contain the same number of conjugated double bonds.
THE MAJOR CAROTENOID PIGMENT - CANTHAXANTHIN
It is a dye, that is compared to the chemical the gives carrots its orange colour.
It is the major carotenoid pigment that is produced by this bacterium
People who suffer from erythropoietic protoporphyria, this is a rare genetic disease. The pigment canthaxanthin aids individuals with this syndrome as it reduces sensitivity to sunlight.
Many people! This pigment is sold as a non-prescribed tanning-pill, known as Orobronze, in Canada. it is also used for the manufacturing of medication and cosmetics
It is used as food colouring, as well as added to animal feed as it enhances the colour of chicken skin, egg yolk, salmon and trout.
Canthaxanthin is a dye similar to the carotenes in vegetables such as carrots. It deposits in the skin to produce an artificial "tan." It might protect against sun sensitivity through antioxidant activity.
