Effects of sodium dodecyl sulfate of polyphenoloxidase

Journal Article · Sat Apr 01 00:00:00 EST 1989 · Plant Physiology, Supplement; (USA)

OSTI ID:6874601

Moore, B M; Flurkey, W H ^[1]

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1. Indiana State Univ., Terre Haute (USA)

The effects of sodium dodecyl sulfate (SDS) on the enzymatic and physical characteristics of purified broad bean polyphenoloxidase (PPO) were examined. A sigmoidal increase in PPO activation was observed with increasing SDS concentrations. Half maximal activation occurred at .9 mM SDS well below the CMC of 3.5 mM. No apparent changes in the Km for catechol, pH optimum, of I{sub 50} for tropolone were observed in the presence vs absence of SDS. Thermal inactivation and binding of {sup 14}C dopa increased in the presence of SDS. Analytical ultracentrifugation and HPLC-SEC indicated that SDS did not change the apparent size of the PPO under nondenaturing conditions. Scanning fluorescence spectroscopy showed an increase in intrinsic trp/tyr fluorescence at approximately the same concentration in which SDS activation began. Further addition of SDS caused a large increase in intrinsic fluorescence. These results suggest the SDS causes an apparent conformational change induced by SDS binding which leads to enzyme activation.

• OSTI ID: 6874601
• Journal Information: Plant Physiology, Supplement; (USA), Vol. 89:4; ISSN 0079-2241
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
OXIDOREDUCTASES
ENZYME ACTIVITY
SODIUM SULFATES
BIOCHEMICAL REACTION KINETICS
CARBON 14 COMPOUNDS
CHEMICAL COMPOSITION
FLUORESCENCE
LIQUID COLUMN CHROMATOGRAPHY
TRACER TECHNIQUES
ALKALI METAL COMPOUNDS
CHROMATOGRAPHY
ENZYMES
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
LUMINESCENCE
OXYGEN COMPOUNDS
REACTION KINETICS
SEPARATION PROCESSES
SODIUM COMPOUNDS
SULFATES
SULFUR COMPOUNDS
550201* - Biochemistry- Tracer Techniques