ABSTRACT

A superbly illustrated review presents the current molecular-level understanding of the key structural complexes of the Gram-positive bacterium using Streptococcus pneumoniae as the teaching. The complementary use of fluorescent antibiotics that inhibit peptidoglycan biosynthesis, or fluorescent indicators of bacterial structure, is a powerful method for the cytological profiling of antibiotic mechanism. Peptidoglycan biosynthesis is fundamentally similar in the Gram-positive bacteria, the Gram-negative bacteria, and the mycobacteria. Many of these structures target the enzymes of peptidoglycan biosynthesis. The enzyme catalysts involved in this dynamic are the target of medical-critical antibiotics. The exterior structure of the unicellular microorganism contains and protects its intracellular structure, while regulating solute ingress and egress. The symbiotic relationship between the mealybug and its Moranella bacterial symbiont derives from the horizontal transfer of genes for peptidoglycan biosynthesis from the genome of the bacterium to the genome of the insect.