Identification and Characterization of the Cyd Gene Locus of Escherichia Coli (Respiration, Membranes, Cloning, Energetics, Cytochromes)
Green, George Neil
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/70542
Description
Title
Identification and Characterization of the Cyd Gene Locus of Escherichia Coli (Respiration, Membranes, Cloning, Energetics, Cytochromes)
Author(s)
Green, George Neil
Issue Date
1985
Department of Study
Biochemistry
Discipline
Biochemistry
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Biology, Microbiology
Abstract
The aerobic electron transport chain of Escherichia coli contains a terminal oxidase, cytochrome d, which is part of a two subunit protein complex that is composed of two additional cytochromes, b(,595) and b(,558). The first mutants affecting the cytochrome d complex (Cyd) have been isolated using two newly developed genetic procedures. These mutations are located in the gene locus, cyd, that mapped to minute 16.5 on the chromosome. The cyd gene and its promoter were cloned and shown to code for both subunits of Cyd. Strains bearing cloned cyd overproduce Cyd by 3- to 4-fold in stationary phase of growth resulting in yellow-green colored colonies of E. coli; purified Cyd is dark green. The color yields a convenient screening procedure for constructing deletions and insertions within cyd. This analysis has localized the region of cloned DNA that codes for subunit II. A spontaneous mutant of cloned cyd overproduces subunit I but does not make subunit II. This strain also overproduces cytochrome b(,558), but produces no cytochrome b(,595) or d. From this strain cytochrome b(,558) was purified in its native state. Purified cytochrome b(,558) is a ubiquinol oxidase, but it does not reduce molecular oxygen. The measured extinction coefficient of 21,000 M('-1) cm('-1) indicates a 1:1 stoichiometry of cytochrome b(,558) per Cyd.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
