Which Fluorescent Molecule Enables Visualization of Living Microorganisms

Question

Which fluorescent molecule enables visualization of living microorganisms?
A) acridine orange
B) DAPI
C) GFP
D) SYBR Green

Accepted Answer

GFP (Green Fluorescent Protein) is commonly used to visualize living microorganisms because it can be expressed in living cells without being harmful or altering the cell's natural behavior. It emits a bright green fluorescent light, making it easy to distinguish cells and track their movements. A) Acridine orange and D) SYBR Green are both useful for staining dead cells, but they can be toxic to living cells, so they are not the best choice for visualizing living microorganisms. B) DAPI is used to stain DNA but is not specific to living cells and requires fixation of the cells.