1. Outline requirements for correct protein folding

2. What is the relationship between a microbe's ease of transmission and the severity of the symptoms of the disease it causes?

3. How did FIV in big cats lead to the discovery of HIV resistant people?

4. Protection from what disease in the past may protect humans from HIV today?

5. What are the preliminary findings in the study of Bavarian children and allergies?

A newly identified bacterial strain needs melrose as a growth factor. To synthesize melrose these bacteria use three enzymes that are encoded by the genes melA, melB and melC in the mel operon. The expression of these three genes is controlled by a regulatory protein MelR. Melrose binds to MelR, and it changes the ability of MelR to bind to the regulatory region of the mel operon. The mel genes are expressed only in the absence of melrose. The regulator MelR, only in the absence of melrose, can bind at the regulatory region of mel operon. Answer the following questions and provide an explanation for each answer

1. Is the mel operon inducible or repressible?

2. Is the MelR a positive or negative regulator?

3. Predict the expression of the mel operon in the following three melR mutants melR1, melR2 and melR3. Choose an answer as regulated or constitutive or no expression, including an explanation.

i. In a melR1 mutant, MelR has lost the ability to bind to melrose.

ii. In a melR2 mutant, MelR cannot bind to the regulatory region irrespective of the presence or absence of melrose.

iii. In a melR3 mutant, MelR binds to the regulatory region irrespective of the presence or absence of melrose.

Is Masturbation advantage or disadvantage?

How frequently should a man masturbate?

“Babies Know: A Little Dirt is Good for You” By Jane E. Brody, NY Times, January 27, 2009 What is this hypothesis called and what does it say? What immune diseases have increased as sanitation has improved? How are intestinal worms being used to treat disease? What role do T cells play in some autoimmune diseases? If you really want a healthy child, how will you accomplish that (according to this article)? What is the best protection against germs?

What unusual cellular characteristic does N. locustae share with the protist Mixotricha paradoxa, the organism discussed in the article “A Russian Doll of Symbiosis?”

Article link: http://eukaryoticmicrobe.blogspot.com/2011/12/russian-doll-of-symbiosis.html

What is the difference between a reversible and an irreversible inhibitor? What is the mode of action for the two most common reversible inhibitors, competitive and noncompetitive? When examined using a Lineweaver-Burk plot, how do each of these inhibitors change the plots? What information can be gained by examination of the intersection of these plots with the X and Y intercepts?

Solution A (1.0 M Sucrose) and solution B (1.0 M NaCl) are separated by a dialysis membrane. If the membrane is spontaneously permeable to Sucrose, NaCl, and Water, what is the INITIAL reaction of Sucrose, NaCl, and Water?

Why are animal cells not totipotent like plant cells? What kind of animal cells is totipotent?

When an Hfr cell conjugates with an F- usually there is no conversion of the F- to Hfr. Occasionally however it can happen and now you can have two Hfr. How can this rare conversion happen?

Regulation in bacteria and phages includes a number of exotic terms with which you can amaze/alarm your friends. Twelve terms are given below followed by twelve statements. Write the letter of the correct term. A single letter is sufficient. Not all letters need to be used, and a particular letter may be used more than once. (15 points)

Term list:

1. temporal control

2. positive control

3. negative control

4. inducible

5. non-inducible

6. repressible

7. constitutive

8. operator

9. repressor

10. effector molecule

11. feedback inhibition

12. suppressor mutation

13. 1. Phenotype with respect to beta-galactosidase synthesis for the partial diploid I+ O+Z+/I- Oc Z-     

___________

2. Phenotype of I+O+Z-/I+Oc Z+

___________

3. Phenotype of I+O+Z-/I-OcZ-

___________

4. Phenotype with respect to synthesis of tryptophan enzymes in the trp operon trpR+ Oc S+ (trpR codes for the repress, S=structural genes).

_______

5. Phenotype of trpR+ O+ S+ in the presence of tryptophan.

________

6. Regulatory molecule must be present at site in DNA (such as promoter) so that transcription can occur ____________.

7. Small molecules that bind to regulatory molecule such as repressor__________

8. Mutation that reverses effect of another mutation at a different site.

____________

9. Type of operons responding to catabolite repression (glucose effect).

___________

10. Post-translational control of biosynthetic pathway.

___________

                    11. Regulatory molecule that binds to operator region in DNA.

13. Describe one supportive measure for severe ARDS.