15. Salivary Proteins

Acquired enamel pellicle (AEP)

organic film covering teeth that appears to protect tooth surface.

Oral floura

Protects salivary proteins from being degraded by amylase.

formation of AEP

formed by selective adsorption of salivary proteins on tooth enamel

Usual function of salivary proteins

Regulate the pH in the mouth.

Acidic proline rich proteins

Most abundant protein in AEP.

Lysozyme

antibacterial salivary protein. secreted by parotid and SMG.

What bond is hydrolyzed by lysozymes?

Breaks the B(1-4) glycosidic bond in bacterial peptidoglycan, weakening gram positive bacteria.

Amylase

Major protein produced by salivary glands, mostly parotid and SMG.

What sugar bond does amylase break?

Cleaved α-1,4 bonds between glucose molecules in starch producing maltose and glucose.

How is amylase inactivated?

Inactivated by the acidic content in the stomach.

Mucins

present in the mucous layer of all epithelial surfaces. Provide lubrication, microbial clearance, and viscoelastic properties to saliva.

Mucins structure

Protein structure characterized by a central region of multiple tandem repeats rich in Ser and Thr.

What property of mucins protect the tissues from desiccation, injury, and microbial assault?

The high degree of glycosylation and potential for hydration.