Pattern recognition receptors - that motions material ingested by a cell

What do toll-like receptors (TLRs) in phagosomal and endosomal membranes typically recognize?

Typically recognize characteristics of nucleic acids that indicate a microbial origin.

How can cells distinguish microbial nucleic acid from normal host nucleic acid based on sequences?

Certain nucleotide sequences are much more common in bacterial DNA than in normal host cell DNA.

How can cells distinguish microbial nucleic acid from normal host nucleic acid based on structure?

The genome of RNA viruses is often double-stranded during the viral replication cycle, and DNA viruses may generate long double-stranded RNA (dRNA) during transcription.

Why are certain toll-like receptors (TLRs) in endosomes or phagosomes not fully functional until the vesicle fuses with lysosomes?

It exposes the contents of the vesicle to low pH and digestive enzymes. This requirement helps prevent inappropriate responses to host cell nucleic acid.