Tsamsa Virus: A New Anthrax Treatment

Lately, there has been a lot of commotion regarding a newly discovered bacteriophage that kills anthrax bacteria.  However, the implications of this phage are not new, and, furthermore, therapies derived from it may not be efficacious for treating advanced stage anthrax infections.

What is anthrax?  Anthrax is a serious infection caused by the gram-positive, rod-shaped Bacillus anthracis bacterium.  It is found naturally in the soil, and affects domestic animals as well as wildlife around the world.  Humans can also become infected with the bacteria.

Colored Scanning Electron Microscope (SEM) image of B. anthracis spores.

How Does Infection Occur?  Infection occurs when the spores, the dormant form of the bacteria, are ingest, in haled, or come into contact with a lesion on the skin.  These infections can occur by eating raw or undercooked meat, drinking contaminated water, or while working with infected animals or animal products, such as wool, hides, or hair.  However, anthrax is not contagious.  The Centers for Disease Control and Prevention have reported rare cases where anthrax has been transmitted from person-to-person via infectious discharges from skin lesions.  Also, a new mode of infection has been reported.  This new mode involves infection following use of contaminated intra-venous needles by drug users.

Diagram courtesy of the Centers for Disease Control and Prevention

Symptoms

Ancient Assassin Plants in Modern Times

Two plant toxins, ricin and abrin, have made their way into the news recently.  A Florida man was recently arrested for allegedly selling abrin to an undercover US federal agent, and a Mississippi man was recently charged for sending ricin-laced letters to government officials, including President Barack Obama.  Both will face criminal charges which could put them in prison for life.

Are these ancient plants still dangerous?  Many people may associate these with antiquated methods of assassination, yet they are still a dangerous threat.  Abrin and ricin are dangerous toxins because there is no antidote for either one.  They work by inhibiting protein synthesis inside of cells leading to cell death.  Abrin comes from the seeds and other parts of the tropical rosary pea plant, and ricin comes from the seeds of castor bean plants.

Toxin Structure  These toxins are similar in structure and function to several bacterial toxins, including cholera, anthrax, Shiga, and diphtheria [1].  All these bacterial toxins represent current health threats and have been of interest in terrorism and warfare.  These toxins consists of two parts, the “A-chain” and the “B-chain”.  The B-chain is responsible for attaching the toxin to the cell.  It contains several carbohydrate binding sites, which can attach to glycolipids and glycoproteins on the outside of cell [2-4].  Once it has attached to the outside of the cell, receptors are activated, which leads to internalization of the toxin into the cell.  Once inside the cell, the toxin is transported to the endoplasmic reticulum.  In the endoplasmic reticulum, ribosomes synthesize proteins.  The A-chain works by removing a specific nucleotide from 28S ribosomal RNA, a part of the ribosome [5-7].  This removal does not disrupt the protein synthesis activity of the ribosome, but it makes it susceptible to spontaneous hydrolysis, chemical reaction in which water breaks apart a molecule, such as a ribosome [8, 9]. The toxin can disrupt ribosomes much faster than the cell can replace them.  Thus, the cell dies because it can no longer produce proteins necessary for its survival and function.

Nefarious History