Open AccessHighly Efficient Genetic Transformation of Bacillus subtilis Attached to Sand Grains
Author(s) -
Michael G. Lorenz,
Barend W. Aardema,
Wilfried Wackernagel
Publication year - 1988
Publication title -
microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.019
H-Index - 179
eISSN - 1465-2080
pISSN - 1350-0872
DOI - 10.1099/00221287-134-1-107
Subject(s) - bacillus subtilis , transformation (genetics) , bacillaceae , microbiology and biotechnology , bacillales , biology , bacteria , genetics , chemistry , gene
Genetic transformation at the solid/liquid interface was studied using Bacillus subtilis 1G20 (trpC2) with a flow-through system of columns filled with chemically pure sea sand. Studies were done at 23 degrees C. In one type of experiment, competent cultures were incubated with sand-adsorbed DNA, and in another, competent cultures were exposed to sand and then incubated with dissolved DNA for transformation. Of the applied cells, around 10% were retained in columns filled with DNA-loaded sand and around 1% in columns with pure sand. Reversible attachment of some of the cells to surfaces of sand grains could be demonstrated. The overall transformation frequencies obtained were 25- to 50-fold higher than in a standard liquid culture procedure. In this standard procedure, transformation was sensitive to DNAase I concentrations above 50 ng ml-1, whereas in sand columns it was resistant to DNAase I concentrations up to 1 microgram ml-1. Quantification of transformants eluting from columns indicated that sand-attached cells detach at some point after DNA binding or uptake.