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A Pass­ing Thought

by Elio

In the cel­e­brated novel The Rebel An­gels, the famed Cana­dian au­thor Robert­son Davies men­tions Ozias Froats, a fic­tional pro­fes­sor po­ten­tially on his way to a No­bel Prize for dis­cov­er­ing that everyone's fe­ces re­flect the maker's per­son­al­ity. He did not have today's ready re­course to metage­nomics (that be­ing still in the fu­ture), so he looked at "ex­tremely thin slices of fae­ces, cut trans­versely, and ex­am­ined mi­cro­scop­i­cally and un­der spe­cial light." He found that each person's spec­i­men re­veals dif­fer­ences in in­di­vid­ual tem­pera­ment. It oc­curred to me that us­ing this same ap­proach could add an­other di­men­sion to fe­cal metage­nomics by de­ter­min­ing the in­tra-turd lo­ca­tion of in­di­vid­ual species. This could read­ily be vi­su­al­ized us­ing spe­cific flu­o­res­cent-la­beled an­ti­bod­ies on thin sections—merely a tech­ni­cal elab­o­ra­tion on Froats' meth­ods.

Sec­tions of Rock­yard Chal­cedony (var. Agate) from Burns, OR. Ex­cept for the col­ors, might a sec­tion through fe­ces look like this? Source

I know lit­tle about how fe­ces are made ("tur­dopoiesis") ex­cept that it in­volves de­hy­dra­tion of the colonic con­tents. In the process, some bac­te­ria are surely dis­placed me­chan­i­cally but oth­ers per­haps turn on their motil­ity ap­pa­ra­tus early in the process to travel to a pre­ferred site, be it the edge or the in­te­rior of the cre­ation. Do those species that cling to the mu­cosal sur­face or in­habit the mu­cus also get car­ried along? Or are they found mainly on the sur­face of the bo­lus? And what about prophages, which may well come to life as the re­sult of bac­te­r­ial stress? Sam­pling for metage­nomics is eas­ier to do with fe­ces than with the in­sides of the gut, but at present we know lit­tle about the geom­e­try of mi­crobe-rich en­vi­ron­ments and their dy­nam­ics.

Froats saw much beauty in his work. He de­scribed what he saw in the sec­tions as "splen­did cut­tings of moss-agate, brec­ciated agate, an ex­tra­or­di­nary beauty rem­i­nis­cent of 'that chal­cedony which John's Rev­e­la­tion tells us is part of the foun­da­tions of the Holy City'." Who knew? Any­how, with in­di­vid­u­al­ized med­i­cine upon us, per­haps stan­dard lab­o­ra­tory tests in the fu­ture may in­clude cut­ting sec­tions of fe­cal sam­ples for mi­cro­scopic eval­u­a­tion. Be­sides, this may give the per­son do­ing the ex­am­in­ing un­ex­pected vi­sual plea­sures.

 

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Mark O. Martin
13 years ago

Elio! How won­der­ful to find a fel­low fan of the late, great Robert­son Davies ("The Dept­ford Tril­ogy" has been very in­flu­en­tial to me). And much *more* won­der­ful to find a mi­cro­bial, if...um...earthy con­nec­tion to the Mi­cro­bial Ma­jor­ity within us all.
As I read your es­say, I didn't dwell upon the "scat"-ological as­pects of it, but was re­minded of the myr­iad mi­cro-mi­cro en­vi­ron­ments to be found within a grain of soil. Dif­fer­ent lev­els of oxy­gen, dif­fer­ent types of nu­tri­ents, dif­fer­ent lev­els of water...no longer a dis­crete num­ber of niches, but a grad­u­a­tion of so many, blend­ing into one an­other. So it is with this hum­ble pack­ag­ing sys­tem of the gut, os­ten­si­bly used to rid the body of not sim­ply waste mi­cro­bial, but myr­iad colonists ("colon"-ists, per­haps?).
It brings me back to William Blake, he of "Au­guries of In­no­cence," who wrote:
"To see a world in a grain of sand,
And a heaven in a wild flower,
Hold in­fin­ity in the palm of your hand,
And eter­nity in an hour."
As Davies' char­ac­ter Froats can di­vine the hu­man tem­pera­ment from such an un­der­ap­pre­ci­ated and un­ex­pected source, do the Small Mas­ters see—and live within— the uni­verse to be found in what we pro­saically flush away?
Such an in­ter­est­ing es­say. Thank you.

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Tim
13 years ago

While I am un­aware of the bac­te­r­ial dis­tri­b­u­tion in a stool sam­ple, there was a rel­a­tively re­cent study in PLOS NTD re­gard­ing the spa­tial dis­tri­b­u­tion of var­i­ous helminth eggs within stool.
http://www.plosntds.org/article/info%3Adoi%2F10.1371%2Fjournal.pntd.0001969
The no­ticed no cor­re­la­tion be­tween the cen­ter of the stool and the sur­face, but for some species did see dif­fer­ences in the lin­ear dis­tri­b­u­tion be­tween front and back.

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marcia stone
13 years ago

My late Jack Rus­sell ter­rier was cer­tain that dog poop was far more valu­able than any hu­mans or cats could pro­duce..
Every­time a dog poops in my neigh­bor­hood, hu­mans run over and scoop it up in a spe­cial bag and de­posit it in an im­por­tant look­ing receptacle.In con­trast, hu­mans go into a closed room and just flush their's away. Al­most the same goes for cats, they use a spe­cial box but in the end that's just flushed as well.
Dog poop is so valu­able that peo­ple are even fined for not de­posit­ing their dog's leav­ings ap­pro­pri­ately.
Saffy the Dog used to stand over her poop and guard it so it wasn't stolen be­fore I picked it up and de­posited it in the spe­cial re­cep­ta­cle. Her be­lief was re­in­foced by the treats young dogs got for de­posit­ing their poop on the side­walk where it wouldn't get lost.
It's pos­si­ble all that col­lected dog poop does con­tain some very spe­cial chem­i­cals and maybe New York City is bal­anc­ing its bud­get by sell­ing them to vi­able mar­kets around the world. Maybe my Jack Rus­sell was onto some­thing. 🙂
Elio replies:
I know you for be­ing so knowledgeable,but didn't know it ex­tended it­self to such weighty mat­ters.

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Robert Murray
13 years ago

Most of the re­ally in­ter­est­ing dis­tri­b­u­tions hap­pen by bac­te­r­ial in­tent in the small in­tes­tine and long be­fore the strag­glers are cast into the pit of the colon for even­tual com­paction, one might hope, into the dis­pos­able turd. The churn­ing must be some­what dis­tress­ing to the ones that still wish to find and hang onto an ep­ithe­lial cell or, when ex­hausted, rest in the ap­pen­dix if not hang onto a nearby piece of veg­etable re­mains. Some may be ir­ri­tat­ing enough (given at­tach­ment) to obey sig­nals from on high and try to get rid of every­one of the crowd — a pat so­lu­tion. It may be hard for more than a few to find their true po­si­tion in colonic life.
Elio replies:
A lovely ex­pla­na­tion of what re­ally may be go­ing on, in­tratur­di­cally speak­ing. We are barely aware of the mir­a­cles hap­pen­ing therein.

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