Comparisonoflysismethods

Comparison of lysis methods

Sonication

• most efficient method of cell fractionation

• problem: heat build up which can denature proteins (proportionate to length of sonication)

• precaution: do on ice and sonicate intermittantly

material: ultrasonication bath or rods

Homogenisation

• best for animal tissue; less suitable for cells

• precaution: do on ice to reduce heat build-up and denaturation

material: drills (polytron), pestle/tube (dounce) bead beaters

Freeze-thaw

• least effective method

• plus: does not denature proteins as much as other methods

material: pestle and mortar, liquid nitrogen

Detergents

• chemical method of lysis

• problems: detergent may inhibit subsequent reactions

• problems: detergent may disrupts protein interactions

no additional material required, just the chemicals and typical tubes