EFFECTS OF EXTERNAL STIMULI ON ENVIRONMENTAL BACTERIAL STRAINS HARBORING AN ALGD-LUX BIOLUMINESCENT REPORTER PLASMID FOR THE STUDY OF CORROSIVE BIOFILMS
Jf. Rice et al., EFFECTS OF EXTERNAL STIMULI ON ENVIRONMENTAL BACTERIAL STRAINS HARBORING AN ALGD-LUX BIOLUMINESCENT REPORTER PLASMID FOR THE STUDY OF CORROSIVE BIOFILMS, Journal of industrial microbiology, 15(4), 1995, pp. 318-328
An alginic acid biosynthesis bioluminescent reporter plasmid, pUTK50,
was transconjugated into environmental strains of Pseudomonas putida,
Pseudomonas fluorescens, and Stenotrophomonas maltophilia. Bioluminesc
ent transconjugates were selected from each strain for investigation o
f environmental stress factors that promote alginic acid exopolymer bi
osynthesis in developing biofilms. Environmental stimuli associated wi
th increased levels of alginate synthesis, in a previously developed o
rganism, P. aeruginosa FRD1, were applied to the environmental strains
. Increased salt concentrations and higher ratios of nitrate vs ammoni
um ions as the limiting nitrogen source induced bioluminescence in FRD
1 and the environmental strains. However, for environmental strains of
P. putida, P. fluorescens and S. maltophilia, polysaccharides were de
tected with low uronic acids content and different structural componen
ts. When tested within a biofilm, S. maltophilia 046 demonstrated exce
ptional adhesive and corrosive properties while alginic acid synthesis
was not high. In most of the environmental strains, periods of increa
sed bioluminescence were induced by external stimuli, but exopolysacch
arides other than alginic acid were expressed. It is hypothesized that
the environmental strains have homologous but nonidentical promoter s
equences which are responsive to certain environmental stimuli and may
control genes necessary for the production of alternative exopolysacc
harides.