The first 4 amide hydrogens and the last 4 carbonyl oxygens cannot participate in helix H bonds.

TLS Online TPP Program

#Id: 8187

#Unit 2. Cellular Organization

Biosynthetic function of animal peroxisomes- 

Synthesis of cholesterol and dolichol 

Synthesis of bile acids in the liver 

Catalyze the first reactions in the formation of Plasmalogens

TLS Online TPP Program

#Id: 8188

#Unit 2. Cellular Organization

Plasmalogens

• most abundant class of PL in myelin sheaths

• Analogous to PC

• Contain an unusual fatty alcohol that is attached through an ether linkage.

TLS Online TPP Program

#Id: 8189

#Unit 2. Cellular Organization

C-terminal peroxisomal signal sequences Ser–Lys–Leu (PTS1)

N-terminal peroxisomal signal sequences slightly longer and partially hydrophobic (PTS2)

TLS Online TPP Program

#Id: 8190

#Unit 2. Cellular Organization

Peroxins

Catalyse peroxisomal protein import by ATP hydrolysis.

TLS Online TPP Program

#Id: 8191

#Unit 2. Cellular Organization

PTS1 signals are recognized by the peroxin Pex5 receptor

PTS2 signals are recognized by the peroxin Pex7 receptor

Neither targeting sequence is cleaved after import.

TLS Online TPP Program

#Id: 8192

#Unit 2. Cellular Organization

Catalase, are synthesized as precursors with PTS1

Thiolase, are synthesized as precursors with PTS2