Lysosomes are organelles that contain digestive enzymes (acid hydrolases). They digest excess or worn out organelles, food particles, and engulfed viruses or bacteria. The membrane surrounding a lysosome prevents the digestive enzymes inside from destroying the cell. Lysosomes can fuse with vacuoles and dispense their enzymes into the vacuole, digesting its contents. They are built in the Golgi apparatus. The name “lysosome” came from the Greek words “lysis” which means dissolution or destruction and "soma" which means body. They are frequently nicknamed "suicide-bags" or "suicide-sacs" by cell biologists due to their role in autolysis. Lysosomes were discovered by the Belgian cytologist Christian de Duve in 1949.

DC-LAMP

• a novel lysosome-associated membrane glycoprotein localized on chromosome 3q26.3-q27. PMID: 9768752

LAMP1

• The lysosomal membrane proteins LAMP-1 and LAMP-2 are estimated to contribute to about 50% of all proteins of the lysosome membrane. PMID: 16973206
• Lysosome-associated membrane protein 1 (LAMP-1) is a glycoprotein highly expressed in lysosomal membranes. PMID: 16972884
• may be a useful marker in newborn screening for lysosomal storage disorders (LSDs). PMID: 9267309

LAMP2

• Lamp-2 occurs to a significant extent in a soluble fraction of rat liver lysosomes. PMID: 9784854
• a marker for lysosomal storage disorders. PMID: 9761240

Rap1

• both Rap1A and Rap1B proteins were localized to late endocytic compartments (late endosomes/lysosomes) in fibroblasts. PMID: 7962206