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Part I. Studies on the Activation of Drosophila Phenol Oxidase. Part II. Studies On Serum Insulin in Normal Subjects and Diabetics


Seybold, William Davidson (1972) Part I. Studies on the Activation of Drosophila Phenol Oxidase. Part II. Studies On Serum Insulin in Normal Subjects and Diabetics. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/WXV5-S223.


Part I

Phenol oxidase is the enzyme responsible for hardening and pigmentation of the insect cuticle. In Drosophila, phenol oxidase is a latent enzyme. Enzyme activity is produced by the interaction of a number of protein components. A minimal activation scheme consisting of six protein components, designated Pre S, S activator, S, P. P' and Ʌ1 is described. Quantitative assays have been developed for the S activator, S, P and P' proteins and these components have been partially purified. Experiments describing the interactions of the six components have been conducted and a model for the activation of phenol oxidase in a minimal system is proposed. Possible mechanisms of the reactions between the constituents of the activating system and potential regulatory mechanisms involved in phenol oxidase production and function are discussed.

Part II

A method has been developed for the partial purification of insulin from human serum. A procedure for the determination of the electrophoretic mobility of serum insulin on polyacrylamide gels is described. An electrophoretic analysis of insulin isolated from a normal subject is reported and in addition to a major band, the existence of a number of minor bands of immunoreactive insulin is described. A comparison of the electrophoretic patterns of insulin isolated from normal and diabetic subjects was carried out and indications that differences between them may occur are reported.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:(Biochemistry)
Degree Grantor:California Institute of Technology
Major Option:Biochemistry
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Mitchell, Herschel K.
Thesis Committee:
  • Unknown, Unknown
Defense Date:26 May 1972
Funding AgencyGrant Number
McCallum FoundationUNSPECIFIED
Record Number:CaltechTHESIS:03212016-102830515
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:9629
Deposited On:21 Mar 2016 20:38
Last Modified:02 Jul 2024 21:09

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