These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Factors affecting quantitative transformation of streptomycin resistance markers in Acinetobacter calcoaceticus.
    Author: Bergan T, Vaksvik AK.
    Journal: Zentralbl Bakteriol Mikrobiol Hyg A Med Mikrobiol Infekt Parasitol; 1983 Apr; 254(2):197-213. PubMed ID: 6586036.
    Abstract:
    Quantitative transformation of Acinetobacter calcoaceticus BD4-Ss exposed to autologous DNA in a liquid system was examined with streptomycin resistance as a marker. The exposure to DNA was terminated by addition of DNase at set intervals. The variables tested were concentrations of autologous Sr-DNA, exposure time, growth phase, recipient cell density, and the pH of the liquid transformation system. The ratio of transformants to total number of recipient cells (T/R-ratio) was proportional to the DNA concentration up to a level of about 10 micrograms/ml. There was a constant increase of transformant numbers upon time of exposure. The T/R ratio was highest at the early growth phase, but the total number of transformed cells per ml culture aliquot was only raised by a factor approximately 10 from the earlier to the later growth phases and non increase was observed in recipients grown for more than 3 hours. There was a marked relationship between the relative number of transformants per total number of recipients in that the T/R-ratio was markedly higher with fewer cells per ml in the transformation broth system where exposure to DNA occurred. The transformation was higher at a pH of 7.3 than 7.0. The results enabled definition of the optimal test system for quantitative transformation of A. calcoaceticus with the strain BD4 as recipient.
    [Abstract] [Full Text] [Related] [New Search]