Question

select all that apply
which two of the following types of proteins are found in the periplasmic space of gram-negative bacteria?

□ enzymes that synthesize peptidoglycan

□ integral membrane proteins

□ porin proteins

□ transport proteins

□ exoenzymes

Explanation:

1. Enzymes that synthesize peptidoglycan: The periplasmic space of Gram - negative bacteria contains enzymes involved in peptidoglycan synthesis. Peptidoglycan is a major component of the bacterial cell wall, and the enzymes for its synthesis are located in the periplasm to facilitate cell wall construction.
2. Transport proteins: Transport proteins in the periplasmic space are involved in the uptake and efflux of various molecules. They help in transporting nutrients, ions, and other substances across the outer membrane and into the cytoplasm or in the reverse direction.
3. Integral membrane proteins: Integral membrane proteins are embedded in the cell membrane (either the inner or outer membrane), not in the periplasmic space. The periplasmic space is the region between the inner and outer membranes, and integral membrane proteins are part of the membrane structure.
4. Porin proteins: Porin proteins are located in the outer membrane of Gram - negative bacteria, forming channels for the passage of small molecules. They are not found in the periplasmic space but in the outer membrane.
5. Exoenzymes: Exoenzymes are enzymes that are secreted outside the bacterial cell to break down macromolecules in the external environment. They are not located in the periplasmic space.

Answer:

enzymes that synthesize peptidoglycan, transport proteins