Nanodes?
"Nanodes (much smaller than microbes) live within our atmosphere, and have for many billions of years."
I found various links to "nanodes" - a type of orchid, a species of Coleopters, a kind of parrot, and a Japanese outfit called "Nano Device and System Research Incorporation" - but nothing relating to organisms in the upper atmosphere.
Dyslexia stikes again? - I think you meant nanoBes...