Fine Reading: Mycobacteria Grow and Divide...

...Like Other Bacteria – Only Differently
 

by Elio
 

Tubercle bacilli, scanning EM. Source: Zi­mek Systems

I've been trying to find a simile for mycobacteria, those outliers in the world of bacterial pathogens (and sa­pro­bes). Maybe they are to other bacteria like cacti are to other plants. They're not exactly spiny but they sure are different. (Come up with your own simile, if you wish.) They're acid fast, resistant to drying, slow growing, and – to round out the picture – cause diseases like TB and le­prosy that, if not unique, are not your ordinary infections. But, just as cactuses are green and have leaves, so do mycobacteria share a common physiological repertoire with other bacteria.
 

A recent review by Hett and Rubin tells much of what is known about the differences and similarities between mycobacteria and the rest of the bacteria with regard to cell structure, cell division, and growth. Also discussed are the particular challenges faced by mycobacteria, such as entering and escaping from dormancy. The writing features a string of refreshingly Socratic questions. Where else would you find queries such as: Are myco­bacteria Gram-positive or Gram-negative? and Why are mycobacteria rods? and Does resusci­tation involve normal homeostatic processes? Twenty-one pages of text and 463 references later, you will have found the answers to these and many other questions central to the mycobacterial way of life.
 

 
 

 
 

Comments

[elio schaechter]

Thanks for pointing out that this is World TB Day. Given that TB is a "social" disease, its eradication, though difficult, is not out of the question.

Elio