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1、一、实验室培养鉴别微生物Millionsofmicrobialspeciespopulatetheworld,butsofaronlyafewhavebeenidentifiedduetotheinabilityofmostmicrobestogrowinthelaboratory.EdgarGoluch,anengineer,andSlavaEpstein,abiologist,aimtochangethis.Thepair,bothresearchersatNortheasternUniversity,hasdevelopedadevicethatallowsscientiststo
2、cultivateasinglespeciesofbacteriathatcanthenbestudiedandidentified.Goluch'spreviousresearchdevicesincorporatedpermeable（冇渗透f生白勺）membraneslthatallowsequestered2bacteriatobeexposedtothenutrients3andmolecules4oftheirnativeenvironment.Butnaturalcompetitionbetweenspecies,eveninthewild,hassofarlimitedt
3、henumberofspeciesofbacteriathatbiologistshavebeenabletoisolate5withthesemethodsandintraditionallabsettings.GoluchandEpstein'sdevice,detailed6inapaperreleasedJuly1inthejournalPLOSONE,solvesthisproblem.Thisnewdevicepermitsjustasinglebacterial7celltoenteraninnerchamber8containingafoodsource,towhicht
4、heonlyaccessisamicroscopic9passagewayjustslightlynarrowerthanasinglecell.Thepassagewayissosmallthatthefirstcelltoenteritgetsstuck,blockingentrybyanyothercellorspecies.Onceinside,thiscellpro-liferatesasinpreviousdevices,andwhenitdoesitfillsuptheinnerchamberwithapure,single-speciessample,sinceitisi
5、solatedlOfromcompetitionfromotherspecies.Inthepaper,theteamdemonstratesthedevice'sabilitytoseparatemixturesofcelltypesinalaboratorysetting.Inoneexperiment,theresearchersseparatedtwodifferentbacterialspecieswhosecellsareslightlydifferentsizes-E.coliandP.aueruginosa.Inasecondexperiment,theyisolated
6、acombinationofsimilarlysizedbutdifferentlyshapedspeciesthatcommonlyshowuptogetherinthemarinellenvironment-Roseobactersp.andPscyhoserpenssp.Finally,theyusedthedevicetoseparatecellsofthesamespeciesthathadbeendifferentiallytaggedtogloweitherredorgreen.Thisfinalexperimentvalidatesl2thehypothesisthatt
7、hecellsgrowninsidethefoodchamberaredaughtersofthesinglecellcaughtintheentryway.EpsteinwilltestthedevicesinthebiologicalsettingbeginningthismonthduringaresearchtriptoGreenland.Goingforward,fundingfromanInstrumentDevelop
