Have you ever read Small Things Considered?  It is the Microbe Blog put out by American Society for Microbiology.  A recent blog describes how phages infect bacteria.  It seems that some icosahedral phages “grow” a tail after absorption.  These describe Gram negative bacteriophage, but Gram positive bacteria have a thicker peptidoglycan cell wall.  I wonder if any cryo EM has been taken on Mycobacteriophage adsorbing and infecting?

http://schaechter.asmblog.org/schaechter/2014/01/bridges-across-the-periplasmic-moat.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+schaechter+%28Small+Things+Considered%29