what is an unculturable bacterium? While at first glance, there
appears to be a contradiction in the title of this review, in this
context, “unculturable” indicates that current laboratory culturing
techniques are unable to grow a given bacterium in the laboratory.
That all organisms must be growing in their natural environment is
axiomatic;thatmanywecannotcurrentlygrowwillbeculturedinthe
futureiscertain.Therefore,“unculturable”doesnotmean“cannever
becultured”but,rather,signifiesthatwelackcriticalinformationon
their biology, and this presents both challenges and opportunities.
Theseopportunitiesarethechancetolearnthemolecularprinciples
behind this recalcitrant growth, allowing us to add that information
toourrepertoireofmicrobiologicaltechniquesandgainingaccessto
previously hidden metabolic diversity that will provide new natural
products and reveal factors that can contribute to both ecological
balanceandhosthealth.Thisreviewexaminestherecentapproaches
thatmicrobiologistsareemployingtoconvertcurrentlyunculturable
bacteria into cultured isolates in the laboratory while concurrently
beginningtodiscoverthemechanismsbehindtheirapparentuncul-