there are microorganism in their cells symbiosis 24

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: heir cells. symbiosis? 24 Thursday, December 6, 12 How to study microbes • Key questions about microbes in environment: Who are they? (i.e., what kinds of microbes are they) What are they doing? (i.e., what functions and processes do they possess) 25 Thursday, December 6, 12 Studying the microbe-like entities in the aphid gut Field Observations not exceptionally helpful because the appearance of microorganism is not a good indicator of "what they are" appearance is very homoplastic Appearance of limited value 26 Thursday, December 6, 12 Studying the microbe-like entities in the aphid gut Culturing Field Observations great plate anomaly: can't grow a lot of the microbe (that lives in the aphids' gut) in the lab Key bacteria in aphid gut have not been cultured Appearance of limited value 27 Thursday, December 6, 12 Studying the microbe-like entities in the aphid gut DNA CSI-style Culturing Key bacteria in aphid gut have not been cultured Field Observations Appearance of limited value 28 Thursday, December 6, 12 • Who Are They? 29 Thursday, December 6, 12 PCR and phylogenetic analysis of rRNA genes DNA extraction PCR Makes lots of copies of the rRNA genes in sample PCR sample run a PCR Phylogenetic tree rRNA1 Sequence alignment = Data matrix Yeast C A C A C T A C AG AGA C T AG rRNA1 5’ ...TACAGTATAGGT GGAGCTAGCGATC GATCGA... 3’ T E. coli Humans A Yeast E. coli rRNA1 Sequence rRNA genes Humans A T build an alignment AG T build a tree: it can tell you what kind of organisms there in the sample 30 Thursday, December 6, 12 31 Thursday, December 6, 12 related to E.Coli (in the same family) 32 Thursday, December 6, 12 • What Are They Doing? it doesn't really tell us the function b/c microbe can change pretty rapidly (even though they are in the same family) in order to know, we use experimental study. a new way is to sequence the WHOLE genome and not just the ribosomal...
View Full Document

This document was uploaded on 04/13/2013.

Ask a homework question - tutors are online