Bacteria May have peptidoglycan cell wall Have ester linked lipids Methanogens Methane-producing archaea (methanogens) are strictly anaerobic convert substrate to methane Archae Have RNA polymerase similar to eukaryotes Have ether linked lipids in their cell membranes Solution Bacteria May have peptidoglycan cell wall Have ester linked lipids Methanogens Methane-producing archaea (methanogens) are strictly anaerobic convert substrate to methane Archae Have RNA polymerase similar to eukaryotes Have ether linked lipids in their cell membranes.