Design of rapid screening technique for identification of Shewanella oneidensis iron-reduction deficient mutants

Introduction : Microbial metal reduction forms the basis of alternate bioremediationstrategies for reductive precipitation and immobilization of toxic metals such as Fe(III). Objectives : A rapid screening techniques were developed to identify Shewanella oneidensis MR-1 respiratory mutants unable to reduce Fe(III) as anaerobic electron acceptor. Method : The Fe(III) reduction-deficient mutant screening technique was based on the observation that wild-type Shewanella Oneidensis produced a dark blue precipitate on its colony surface during growth on Fe(III) while colony arising from
mutagenesis did not.

Result : Three of the mutant strains were unable to produce the dark blue precipitate
after tested for anaerobic growth in a 96-well plates. The result present study shows that Shewanella Oneidensis iron-reduction deficient mutants was generated and yet
retained the ability of reducing Fe(III) to Fe(II).

Conclusion : This study describes the development of a mutant screening technique and its application to identify a set of mutants in a metal-reducing member of the genus Shewanella in anaerobic condition which is use in a bioremediation process.