Degree Type

Dissertation

Date of Award

1986

Degree Name

Doctor of Philosophy

Department

Food Technology

Abstract

A method for the production of protoplasts from Propionibacterium freudenreichii and regeneration of the protoplasts to walled cells was developed. A cell population that consisted of >99.9% osmotically fragile cells was produced by incubating mid-exponential phase cells with lysozyme in an osmotically stabilizing environment;Regeneration of the protoplasts to walled cells took 21 to 28 days, and occurred in soft agar overlays. Regeneration agar consisted of sodium lactate agar supplemented with sucrose and gelatin. The use of soft agar overlays was required for efficient regeneration of the protoplasts, as was the presence of sucrose and gelatin in the medium. Regeneration frequency was calculated by determining the ratio of regenerants to the initial population of whole cells. Regeneration frequencies were usually in the range of 10 to 30%, although occasionally frequencies as high as 85% were obtained.

DOI

https://doi.org/10.31274/rtd-180813-6812

Publisher

Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/

Copyright Owner

LeAnn R. Baehman

Language

en

Proquest ID

AAI8703685

File Format

application/pdf

File Size

122 pages

Included in

Microbiology Commons

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