1. Study on biofilm forming bacterial community isolated from environment
Saheli Ghosh,Asifa Qureshi*,Hemant.J.Purohit.
Environmental Genomics Division,CSIR-National Environmental Engineering Research Institute,Nehru Marg,Nagpur
*Corresponding author-Dr.Asifa
Introduction
Biofilms are sticky,surface(any surface exposed to
water)adherent microbial communities encased in
a matrix of proteins,polysaccarides &nucleic acids
etc.
They are ‘boon’ for environment as they are
employed in the bioremediation of persistent
organic compounds(POP) & ‘curse’ as they cause
threatening diseases.
Results
Biofilm’s response to iron Biofilm’s response to Nitric oxide
Microtiter plate images of
Inducer(Iron) Inhibitor(Nitric oxide using SNP
as NOdonor)
Higher retention of crystal violet occurs in inducer plate as compared to
inhibitor plate
Gel images of RAPD srDNA PCR
Isolation of biofilm forming bacteria by pure culture methods.
Conclusion:
From RAPD it is concluded that the isolates contains many variants.
From biofilm induction assay it can be concluded that
Iron induces biofilm formation in SA-36 isolate.but inhibits
biofilm formation of the unknown isolate.
From biofilm inhibition assay it can be concluded that
High NO conc inhibits biofilm formation in SA-36,unknown
isolate (Experiments are going on and these methods needs to
be optimised.)
Aim
To isolate biofilm forming bacteria from different surfaces and study the effect of inducer & inhibitor molecules on biofilm formation.
Recommendation
An inducer or inhibitor may induce biofilm formation in a particular species or may inhibit in other species.So we can recommend that any iron compound may be used to induce biofilm formation in Staphylococcus sp and Nitric oxide may be used to inhibit monospecies biofilm formation.
Methods
Sample collection &isolation by streak plate method.
96 well microtiter plate assay & O.D measurement at490nm to
check biofilm formation and selected high biofilm forming isolates
such as SA-36(Staphylococcus sp),Unknown isolate.
Genomic DNA isolation,RAPD,16srDNA PCR & sequencing for
the identification of the + biofilm forming isolates.(Sequencing
results are yet to come).
Biofilm induction assay using Iron (ferric citrate
conc=12.5,25,50,100,200µM) & Inhibition assay using Nitric
oxide(Sodium nitroprusside as NO donor conc=25nM to50mM).
Acknowledgements
The authors greatly acknowledge NEERI & CSIR for providing necessary facilities and funding.
Referrences
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