RETRACTION
Volume 66, no. 8, p. 3234–3240, 2000, https://doi.org/10.1128/AEM.66.8.3234-3240.2000. The authors hereby retract this article. The authors have been alerted that Figure 4 does not accurately reflect the experimental data. Specifically, the tops of several wells on the left and right blots appear to be duplicated although the blots purport to represent different samples.
The first author assumes all responsibility for this anomaly. Since the original blots are no longer available, it is not possible to submit a corrected figure.
The authors sincerely regret this problem necessitating retraction of this article.