What structure is an adaptation that helps certain bacteria ward off attack by white blood cells?
1 Answer
Glycocalyx
Explanation:
Taken from a comment made by Ella Labasbas
Glycocalyx is the first-line of defense of most bacteria. It is a covering that is made up of glycoprotein-polysaccharide complex, materials which can also be found on the outer surface of plasma membrane.
The advantage of having these complex is that it creates a "fuzzy" or rough texture to the surface of the bacterial cell. Since it is an additonal structure in the bacteria, leukocytes find it difficult to attack or target the cell itself. This accounts for the ability of some virulent types to resist antibiotics, specifically when administration is not completed for at least 7 days. Furthermore, these glycocalyces allow the bacterial cell to adhere too much in any surface, for instance human skin, bathtub.
Bacteria with an outer covering like glycocalyx are those that are also capable of creating biofilm, which can be observed as a shiny covering in a colony surface when you prepare a bacterial spread in a petri dish with selective media. Like in my field, Vibrio parahaemolyticus creates a biofilm when it is plated in TCBS. This species is capable of infecting shrimps particularly the Penaeus monodon and Litopenaeus vannamei.
In addition, Leukocidins. chemicals secreted by some bacteria, are chemicals that kill the white blood cell upon phagocytosis. In reality, there are a lot of mechanisms bacteria can evade the host defenses. Some kill the WBC, some inhibit phagocytosis, etc etc.
