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Investigations of Some "Unknown" Mutants of Neurospora crassa


Dubes, George Richard (1953) Investigations of Some "Unknown" Mutants of Neurospora crassa. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/WYR6-7736.


A sample of 16 previously "unknown" mutants of Neurospora crassa was studied. Five of these were shown to be double mutants. The growth requirements of 19 of the 21 single-gene mutants available then from these "unknowns" were at least partially defined chemically. Of these 19, three have been classified as serineless, two as asparagineless, two as pyramidineless, two as succinicless, and one each as aceticless, arginineless, aromaticless, asparticless, homoserineless, leucineless, methionineless, methionine-adenine-cystineless, p-aminiobenzoicless, and slow-grower. These had been classified as "unknowns" apparently for various reasons, such as: (1) inhibitions from normal metabolites, (2) complex requirements for double-mutant "unknowns," and (3) absence of active compound from chemically defined mixtures previously used. Some of these mutant genes have been located genetically. These results have been discussed briefly with reference to the hypothesis of the "unifunctionality" of the gene.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:(Genetics and Biochemistry)
Degree Grantor:California Institute of Technology
Major Option:Biology
Minor Option:Biochemistry
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Mitchell, Herschel K.
Thesis Committee:
  • Unknown, Unknown
Defense Date:1 January 1953
Record Number:CaltechETD:etd-04222003-143216
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:1449
Deposited By: Imported from ETD-db
Deposited On:22 Apr 2003
Last Modified:18 May 2023 22:31

Thesis Files

PDF (Dubes_gr_1953.pdf) - Final Version
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