COMBINED NOTES!

    The name of our bacteria is Arthobacter Globiformis. They are coryneform bacteria that are characterized by their pleomorphism (ability to change shape) and gram variability (ability to change from gram negative to gram positive). Their life cycle is marked by two distinct cycles. When the cultures are young, cells are slender, gram-negative rods. Jointed rods can be seen after about 1 or 2 days. After about 30 hours, though, the cells have become very short, gram-positive rods and coccoids. Arthrobacteria are nonsporulating and are members of the actinomycete branch of the gram-positive bacteria. They also exhibit a weak motility that is almost always overlooked.

    Arthrobacteria are pretty nutritionally versatile. They use a variety of substrates in their oxidative metabolism. These include nicotine, nucleic acids, and various herbicides and pesticides. Most species of Arthrobacter are obligate aerobes, but they always exhibit a pure respiratory, never fermentative metabolism. They do not have a flagellum. They are your basic soil bacteria, and form colonies on blood agar.

    Arthrobacteria help reduce hexavalent chromium in soil and work against agricultural pesticides. Hexavalent chromium causes irritations in humans. Arthrobacter can grow in the presence of hexavalent chromium and can also reduce the chromium to trivalent chromium. Trivalent chromium is the form of hexavalent chromium that is less toxic. Arthrobacter works with Streptomyces to create a synergistic relationship. They degrade the organophosphate insecticide diazinon, to use as energy and carbon. Chromium is widespread throughout the environment because of its use in dyes, pigments, refractory material, leather tanning, and electroplating.   

    They range in color from yellow to white, and are usually about 2 millimeters in diameter. They do not have endospores, and are mesophilic, which means they thrive in moderate temperatures from about 25-40 degrees Celsius. In 2003, the energy and growth of two Arthrobacteria were investegated. Arthrobacter globiformis had both acetate and ethanol producing fermentation processes for anaerobic growth. In the two Arthrobacteria, respiratory nitrate reductase activity was detected in the strains. The tested strains did not use the substitute electron acceptors fumarate, dimethylsulfoxide or trimethylamine-N-oxide.

Arthrobacter Globiformis's lineage is as follows:

-Cellular Organisms

-Bacteria

-Actinobacteria

-Actinobacteridae

-Actinomycetales

-Micrococcinae

-Micrococcaceae

-Arthrobacter

-Arthrobacter Globiformis