68Trichodermapolysporumselectivelyinhibitswhi

RESEARCHOpenAccessTrichodermapolysporumselectivelyinhibitswhite-nosesyndromefungalpathogenPseudogymnoascusdestructansamidstsoilmicrobesAmanpreetSingh1,EricaLasek-Nesselquist2,VishnuChaturvedi1,3andSudhaChaturvedi1,3*AbstractBackground:Pseudogymnoascusdestructans(Pd),thecausativefungalagentofwhite-nosesyndrome(WNS),hasledtothedeathsofmillionsofhibernatingbatsintheUnitedStatesofAmerica(USA)andCanada.EfficientstrategiesareneededtodecontaminatePdfromthebathibernaculatointerruptthediseasetransmissioncyclewithoutaffectingthenativemicrobes.Previously,wediscoveredanovelTrichodermapolysporum(Tp)strain(WPM39143),whichinhibitedthegrowthofPdinautoclavedsoilsamples.Inthepresentinvestigation,weusedculture-basedapproachestodetermineTp-inducedkillingofnativeandenrichedPdinthenaturalsoiloftwobathibernacula.WealsoassessedtheimpactofTptreatmentonnativemicrobialcommunitiesbymetagenomics.Results:OurresultsdemonstratedthatTpattheconcentrationof105conidia/gsoilcaused100%killingofnativePdinculturewithin5weeksofincubation.A10-foldhigherconcentrationofTp(106conidia/gsoil)killedanenrichedPdpopulation(105conidia/gsoil).The12,507fungaloperationaltaxonomicunits(OTUs,dominatedbyAscomycotaandBasidiomycota)and27,427bacterialOTUs(dominatedbyAcidobacteriaandProteobacteria)comprisedthenativesoilmicrobesofthetwobathibernacula.NosignificantdifferencesinfungalandbacterialrelativeabundanceswereobservedbetweenuntreatedandTp-treatedsoil(105Tpconidia/gsoil,p≤0.05).Conclusions:OurresultssuggestthatTp-inducedkillingofPdishighlyspecific,withminimaltonoimpactontheindigenousmicrobespresentinthesoilsamples.ThesefindingsprovidethescientificrationaleforthefieldtrialsofTpintheWNS-affectedhibernaculafortheeffectivedecontaminationofPdandthecontrolofWNS.Keywords:White-nosesyndrome,Pseudogymnoascusdestructans,Trichodermapolysporum,Biologicaldecontamination,Biocontrolagent,Selectiveinhibition,Bathibernacula,Nativesoilmicrobiota,MetagenomicsBackgroundPseudogymnoascusdestructans(Pd),theetiologicalagentofwhite-nosesyndrome(WNS),hascausedsignificantreductionsinhibernatingbatpopulationsacrosstheUSAandCanada[1–6].MortalitywasfirstobservedinhibernatingbatsinHowesCavenearAlbany,NewYork(NY),in2006,andhassincespreadextensivelyto32USstatesand7Canadianprovinces[7].RecentlyPdwasdetectedinalittlebrownbat(Myotislucifugus)asfarawayasWashingtonState[8].Severalspeciesofbatsarealreadythreatenedwithextinction,includingMyotislucifugus(littlebrownbat),Myotissodalis(Indianabat),andMyotisseptentrionalis(northernlong-earedbat)[3,9].Pseudogymnoascusdestructans,apsychrophilicfungus,iswelladaptedtogrowinthecoldconditionsprevailingincavesandmines[2,10].Ithasbeenshowntosecreteproteolyticenzymessimilartothefungithatcauseskininfections(dermatophytes);[2]andhasaclonalpopula-tionintheUSA[11–13].Lowbodytemperature,alongwithreducedimmunesysteminhibernatingbats,providestheoptimalgrowthenvironmentforPd[14–17].*Correspondence:[e-mail]1MycologyLaboratory,WadsworthCenter,NewYorkStateDepartmentofHealth,120NewScotlandAvenue,Albany,NY12208,USA3DepartmentofBiomedicalSciences,SchoolofPublicHealth,UniversityatAlbany,Albany,NY,USAFulllistofauthorinformationisavailableattheendofthearticle©TheAuthor(s).2018OpenAccessThisarticleisdistributedunderthetermsoftheCreativeCommonsAttribution4.0InternationalLicense(),whichpermitsunrestricteduse,distribution,andreproductioninanymedium,providedyougiveappropriatecredittotheoriginalauthor(s)andthesource,providealinktotheCreativeCommonslicense,andindicateifchangesweremade.TheCreativeCommonsPublicDomainDedicationwaiver()appliestothedatamadeavailableinthisarticle,unlessotherwisestated.Singhetal.Microbiome(2018)6:139[18–20].Thus,aninfectedhibernaculumcouldremaincontaminatedwithPdforprolongedperiodsoftimeandserveasthefocifornewinfections[21].MathematicalmodelshavepredictedthatreducingPdincavesandminesmaypreventWNS-associatedbatmortality[20,22].Currently,effortsarebe-ingdevotedtothedevelopmentandtestingofchemicalandbiologicalagentsfortheeffectiveeradicationofPdfrombathibernaculaandhibernatingbats.Althoughthesecontrolstrategiesappeartobepromising,theyarenotbeingusedforthelarge-scaledecontaminationofhiber-nacula,becauseofthelikelyoff-targeteffectsonthenativemicrobialcommunities[23–27].ConsideringthemassmortalityofbatscausedbyWNSandtheeconomiclossof22.9billiondollarstoagriculturalpestcontrolintheUSAannually[28],imminentstepsareneededtodecon-taminatePdfrombathibernaculaandbreakitstransmis-sioncycle.Previously,wecharacterizedanovel,psychrotolerantTrichodermapolysporum(Tp)strain(WPM39143)fromtheWilliamPreserveMine,UlsterCounty,NY,oneoftheminesattheepicenteroftheWNSzoonotic[29].Tpgrewwellatlowtemperaturesof6–15°CandinhibitedPdinlaboratorymediaandautoclavedsoilsamples[29].ThepresentstudyaimedatfurtherevaluationofTpasaneffectivebiocontrolagentagainstPd.Speci