Analysing the Metabolic Capabilities ofDesulfovibrioSpecies through Genetic Manipulation

introduction Sulfate-reducing bacteria (SRB) are an environmentally significant group belonging to the anaerobic delta-Proteobac tcria that respire sulfate forgrowth.From an industrial standpoint.SRB pose a threat through corrosion of ferrous metals and production of toxic sulfides.The more positive aspects Utile metabolism of the SR I3 include a robust but poorly understood hydrogen metabolism that is of interest to alternative energy studies.SR I3 also immobilize a number of heavy metals through sulfide precipitation or through changing the redox state of the metal, and thus its solubility.When metals are made less soluble.as i s the ease with chromium (COVI)toCr( 111))oruranium ( VI ) to LitiV )), toxicity is reduced by limiting biological availability.Despite the economic and environmental impacts associated with SRB activities, our current knowledge of their metabolism is inadequate.Among the SRB.members of the Desuffovibrie genus have received most attention because these strains arc grown most readily in pure culture.Therefore.Desulfovibrio strains have been the focus of biochemical and biophysical analyses: however, genetic studies have been more difficult.Over the past 15 years.progress has been made in developing techniques for DNA transformation.gene mutagenesis and over-expression, and protein tagging.Ten years have passed since the last genetics of SRB review by van Dongen (1995).and the complete genome sequences of a few strains are now available (Heidelberg et al.. 2004).This review highlights the 0.11TC11( advances in the genetic manipulation of Desullovibrio species -T,) whom correspondence may he addressed walljitmissouri.edutAbbreviations: 511.1.5-1Thorouracil: (*mit.chloramplicnictil resistant: G4 I K. geneticin derivative-.a/().. gene or interest: Conk.gentamycin resistant: KanR.