Alcaligenes Faecalis Case Study

1. Describe the main characteristics of Alcaligenes faecalis. Where is this bacterium naturally found? How large is the genome of Alcaligenes faecalis?

Alcaligenes faecalis is an aerobic nonfermentative, oxidase-positive, nonencapsulated, gram-negative rod. It is so named for its ability to produce an alkaline reaction in certain media. Microscopic analyses revealed that the bacteria are located in the esophagus and intestine of the nematodes Steinernema feltiae, S. carpocapsae, and H. bacteriophora. Nematodes are microscopic organisms that are naturally occurring and present in the soil. According to encyclopedia Britannica Nematodes, also called roundworms are among the most abundant animals on Earth. They occur as parasites in animals and

What is plasmid DNA and why is it important to the host organism? How does plasmid DNA differ from genomic DNA? How can plasmid DNA be used to introduce foreign genes into bacteria? Describe one specific plasmid that can be used for this purpose. In your answer, make sure to identify the size of the plasmid, its normal copy number and any other unique features that it possesses. How can we selectively grow bacteria that contain this plasmid?

Plasmids are circular deoxyribonucleic acid (DNA) molecules that can independently self-replicate. It carries only a few genes. The number of plasmids in a cell contains is generally constant from generation to generation. Plasmids are autonomous molecules and exist in cells as extrachromosomal genomes, although some plasmids can be inserted into a bacterial chromosome, where they become a permanent part of the bacterial genome. They are not essential for the host but may confer a selective advantage. One class of plasmids, colicinogenic (or Col ) factors, determines the production of proteins called colicins, which have antibiotic activity and can kill other bacteria. Another class of plasmids, R factors, confers upon bacteria resistance to

The plasmid and the gene are both cut using restriction enzymes. To incorporate the gene into the plasmid, both the plasmid and gen stuck together by a bacterial enzyme called ligase. The plasmid with the foreign gene can then be inserted into the bacteria

One specific plasmid is pUB110 which is circular whose host is Bacillus subtilis. It has a plasmid size 2.3 kpb and copy number between 20 - 50. We can selectively grow bacteria that contain this plasmid by using selective and differential media. The pUB110 has antibiotic resistance so the cells can be spread on an agar plate containing an antibiotic that would kill the cells that hadE not taken up the plasmid.

3. Eukaryotic genes contain exons and introns. As a result, eukaryotic mRNA must be processed prior to translation. Briefly describe the process of RNA splicing. Do bacteria possess the enzymes responsible for this process? How would you produce a recombinant plasmid containing a eukaryotic gene that could be directly translated by a transformed bacterial cell? Hint: think of the HIV