STABILITY OF MANIPULATED PLASMID DNA IN AQUATIC ENVIRONMENTS

Very little is known about the stability, behavior, and probability of perpetuation of genetically engineered DNA within a microbial communi ty. The prevalence of genetically engineered microorganisms (and hence their DNA) in the environment as a result of deliberate or accidental release has been an increasingly controversial issue during the past few years. In the present study genetically manipulated plasmid DNA wa s seeded into different types of waters to determine its fate over tim e in the presence of naturally occurring bacterial populations. The se eded DNA was rapidly degraded in surface and marine waters. Up to 10 m u g/mL was degraded in a few hours. The DNA was not degraded in water that had no detectable DNAse-producing microflora. No uptake of the DN A by the resident microflora was observed even where the DNA remained undegraded up to 7 days. We can thus extrapolate that, in some aquatic environments, the genetically engineered DNA will be degraded in a ve ry short time and therefore the concerns of uptake of novel genes by t he resident microflora may be overstated. (C) 1996 by John Wiley & Son s, Inc.