Hydrocarbonoclastic bacteria from a polluted harbour in Sicily (Italy): isolation, identification and characterization of their biotechnological potential.

Metabolicspecializationisageneralbiologicalprinciplethatshapestheassemblyofmicrobialcommunities.Hydrocarbonoclasticbacteria(HCB)aremarinebacteriathatarespecialisedinhydrocarbondegradationandusehydrocarbonsalmostexclusivelyasuniqueCandenergysource.HCBbecomedominantinoil-‐impactedenvironmentsandareparticularlyadaptedforremovalofhydrocarbonsfromcontaminatedsitesthroughbioremediationtreatments.ThepetrochemicalsiteofPriolo-‐Augusta-‐Melilli(Sicily,Italy),isaSiteofNationalInterest(SIN)duetohighlevelsofenvironmentalcontaminationofthecoastlineandaspecific"nationalprogramofenvironmentalremediationandrestoration"wasdevelopedinordertoallowremediationandrestorationofcontaminatedsites.Inordertotoidentifythekeyhydrocarbondegradersandexplorethenaturalbioremediationpotentialofthecontaminatedarea,atotalofsixsedimentandseawatercoreswerecollectedinsidethePrioloHarbour(SR,Italy).Afterbiological(bacterialpopulationdiversity,PCR-‐DGGE)andchemical-‐physicalcharacterisation(quali-‐,quantitativemeasuresofhydrocarbonsandheavymetals)sampleswereused,separately,tosetenrichmentculturesonmineralbrothcontainingdifferentmixturesoflinear(C16,C18,C20)andaromatic(phenatrene,pyrene,biphenylanddibenzothiophene)hydrocarbonsandCrudeOil(ArabianLigthCrudeOil).Atotalof159isolates(82fromseawaterand77fromsediments)wereobtained.Thesequencingof16SrDNAshowedthemostoftheisolatesbelongedto,Alcanivorax(44%),Marinobacter(17%)andOleibacter(9%)genera.Dataobtainedfromassaysofbiodegradationrevealedasmoreinterestingbacteriapresentaveryhighpotentialofapplicationinbioremediationtechniques;furthermoredataobtainedgiveadeeperunderstandingofthebiochemicalcausesofmetabolicspecializationandcouldserveasafoundationforthefieldofsyntheticecology,wheretheobjectivewouldbetorationallyengineertheassemblyofamicrobialcommunitytoperformadesiredbiotransformation.