Answer: Based on the staining properties described in the question, the bacteria with a cell wall containing a thin peptidoglycan layer covered with proteins, phospholipids, and lipopolysaccharides are characteristic of Gram-negative bacteria.
Step-by-step explanation:
The staining properties of bacteria described, with a cell wall containing a thin peptidoglycan layer covered with proteins, phospholipids, and lipopolysaccharides, are characteristic of Gram-negative bacteria.
1) Gram-positive bacteria: Gram-positive bacteria have a thick peptidoglycan layer in their cell wall, which retains the crystal violet stain during the Gram staining process. They do not have an outer membrane like Gram-negative bacteria.
2) Acid-fast bacteria: Acid-fast bacteria, such as Mycobacterium tuberculosis, have a unique cell wall structure that contains a high concentration of mycolic acid. This allows them to retain the red-colored carbol fuchsin stain even after acid washes, making them appear red in acid-fast staining.
3) Gram-negative bacteria: Gram-negative bacteria have a thinner peptidoglycan layer in their cell wall, which does not retain the crystal violet stain during the Gram staining process. However, they have an outer membrane composed of proteins, phospholipids, and lipopolysaccharides. After the crystal violet stain is washed away, they take up the counterstain, usually safranin, appearing pink or red under the microscope.
4) Capsulated bacteria: Capsulated bacteria have an additional outer layer called a capsule, which is made up of polysaccharides or polypeptides. This capsule can provide protection and aid in attachment to surfaces. However, the staining properties of the cell wall do not directly relate to the presence or absence of a capsule.