Screening and Characterization of Phylloplane Bacteria Producing Vibrio fischeri Autoinducer

Abstract

Sixty luve blades representing 14 different plant species in the Woods Hole, Massachusetts, area were collected for the irdatlon of phyllopl.ne bacteria employing a leaf-print method on 10% King's B medium supplemented with 100 pghl cyclohesimldc. Colonies that appeared after 2 3 days were overlaid with Laria Agar (pH 7.4) containing approximately 10' cdlslml of BckaicMo c d carrying Mbriofirckm' hu operon with a 250-base pair non-polar deletkm hr W. Presumptive autoinducer-producing bacteria were isolated from the spots of biolnminescens in the overlaid plates. These kinds of phylloplme bacteria represented approximately less than two percent of the total Ieaf-sulrce bacteria Based on preliminary observation of cdony morphology and limited physiologkd assays, they were two main groups of phylloplane bacteria belonltiag to either Xuntkmona sp. or A b n 4 ~q1vh gw, Accenlda(lty, thb method bas the potential to be developed into a rapid and reliable di8gnostic test, to study the distribution u well u relative abundmre of certain strains or p a t h n of phytloplane bacteria.