Gram-positive virulation and biofilm formation

[gkaz4]

Hi. I have been making research regarding Gram-positive bacterial pili in S. pyogenes and S. pneumoniae.

I was wondering if someone could help me with this question:
Are there any morphological differences between the lower part of the respiratory tract and the nasopharynx? Maybe they have different epithelia with crude or soft properties?

I am standing the flexibility of the bacterial pili and i was wondering if i could substantiate that in order for a bacterium to colonize the nasopharynx epithelia (mucus) should be more flexible than colonizing the lower parts of the respiratory tracts.

Thank you all in avdance