Moderately Curved Bacterial Rods

Rigid poles appear to be the basis of cylinder elongation, a point made many times in this book. The existence of two rigid inert poles on the ends of a cell does not imply that the rod-shaped portion of the cell has to be straight. To understand this, the reader can form a cylindrical soap bubble by connecting a soap bubble between two rigid solid supports, and then adjusting the air pressure until the cylindrical shape is achieved (see Koch, 1990a and Figure 11.1). I have demonstrated this in...

The Coping Strategies Of Hiv Htlvi And Htlvii

HTLV-I and HTLV-II are both retroviruses, of the subclass oncornaviruses that propagate primarily in human T lymphocytes. The former parasitizes CD4-bearing helper T cells and the latter, CD8-bearing cytotoxic T cells. (Hollsberg and Hafler, 1996). HIV is a retrovirus of the subclass, lentivirus, and both it and the oncornaviruses incorporate their reverse transcribed double-stranded DNA into a random chromosome of a human cell as the heart of their survival strategy. Both classes of virus...

Mrsa Methicillinresistant Staphylococcus Aureus

The other case of an apparently new evolution of an antibiotic is the emergence of methicillin resistant Staphylococcus aureus (MRSA). Although MRSA has been very important clinically since 1961, there is reason to believe that the basic mecA gene, encoding PBP 2' evolved from an existing PBP in the distant past as a supplement to the normal group of PBP. It is reasonable to imagine that PBP 2' would be less susceptible to inactivation by p-lactams and protect against natural lactam antibiosis...

Spirochetes

How spirochetes achieve a spiral shape can be partially explained on a combined architectural, kinetic, and mechanical basis. Available ideas are summarized in this section. The special mechanism depends on internal flagella and on a flexible peptidoglycan wall. The major genera of spirochetes include Spirocheata, Treponema, Borrelia, and Leptospira. These genera include the causative agents of syphilis, yaws, Lyme disease, African relapsing fever, periodontal disease, and leptospirosis. All...