Search results
Results from the WOW.Com Content Network
Bacteria produce pigments such as carotenoids, melanin, violacein, prodigiosin, pyocyanin, actinorhodin, and zeaxanthin. Cyanobacteria produce phycocyanin, phycoerythrin, scytonemin, chlorophyll a, chlorophyll d, and chlorophyll f. Purple sulfur bacteria produce bacteriochlorophyll a and bacteriochlorophyll b. [11]
The umbilicus, or navel, is an area of the body that is rarely exposed to UV light, soaps, or bodily secretions [8] (the navel does not produce any secretions or oils) [9] and because it is an almost undisturbed community of bacteria [10] it is an excellent part of the skin microbiome to study. [11]
The word bacteria is the plural of the Neo-Latin bacterium, which is the romanisation of the Ancient Greek βακτήριον (baktḗrion), [6] the diminutive of βακτηρία (baktēría), meaning "staff, cane", [7] because the first ones to be discovered were rod-shaped. [8] [9]
Hyperpigmentation can be diffuse or focal, affecting such areas as the face and the back of the hands. Melanin is produced by melanocytes at the lower layer of the epidermis . Melanin is a class of pigment responsible for producing color in the body in places such as the eyes, skin, and hair.
Keratinocytes form a barrier against environmental damage by heat, UV radiation, water loss, pathogenic bacteria, fungi, parasites, and viruses. A number of structural proteins, enzymes, lipids, and antimicrobial peptides contribute to maintain the important barrier function of the skin.
Therefore, in many pathogenic microbes (for example, in Cryptococcus neoformans, a fungus) melanins appear to play important roles in virulence and pathogenicity by protecting the microbe against immune responses of its host. In invertebrates, a major aspect of the innate immune defense system against invading pathogens involves melanin.
This is an accepted version of this page This is the latest accepted revision, reviewed on 2 March 2025. "Skin pigmentation" redirects here. For animal skin pigmentation, see Biological pigment. Extended Coloured family from South Africa showing some spectrum of human skin coloration Human skin color ranges from the darkest brown to the lightest hues. Differences in skin color among ...
Gram-indeterminate bacteria do not respond predictably to Gram staining and, therefore, cannot be determined as either gram-positive or gram-negative. Examples include many species of Mycobacterium , including Mycobacterium bovis , Mycobacterium leprae and Mycobacterium tuberculosis , the latter two of which are the causative agents of leprosy ...