Hi Eric,

I need more information to answer that question. Do you want to detect LPS in biological samples? Do you want to detect LPS from a specific bacteria? LPSs are molecules with a high degree of heterogeneity. 

Thank your Mr Jofre

because i am doing a lab practical about the shiga toxin. They ask me what two main type of toxin in chemical term. I found that they are endotoxin and exotoxin. However, i don't know what are their limitation of detection by molecular method

LPS are macromolecules with a high heterogeneity even between the same specie. The most variable region is the O-antigen. Molecular methods to detect LPS are not available. However it is possible detect LPS by immunowesternblot using specific antibodies. On the other hand, you can detect, by molecular methods such as PCR or southern hybridization, genes associated to LPS biosynthesis such as glycosyltrasnferases, O-Ag ligases and polymerases.

so you mean O-antigen is the most challenge to the molecular method?

How about the exotoxin? is the exotoxin related to the enzyme?

anyways, thanks you of your answer, because it is really helpful, to give me a way to find the answer