An enzyme has a Vmax of 50 micromol product formed (minute x mg protein)-1 and a Km of 10 microM for the substrate. When a reaction mixture contains the enzyme and 5 microM substrate, which of the following percentages of the maximum velocity will be closest to the initial reaction rate?

#Question id: 4148

#Section 3: Genetics, Cellular and Molecular Biology

Which of the following is true about the sorting pathway for proteins destined for incorporation into lysosomes or the plasma membrane of eukaryotic cells?

#Question id: 4149

#Section 3: Genetics, Cellular and Molecular Biology

Glycosylation of proteins inside the endoplasmic reticulum does not involve:

#Question id: 4150

#Section 3: Genetics, Cellular and Molecular Biology

Posttranslational glycosylation of proteins is inhibited specifically by:

#Question id: 4151

#Section 3: Genetics, Cellular and Molecular Biology

The signal sequences that direct proteins to the nucleus are:

#Question id: 4152

#Section 3: Genetics, Cellular and Molecular Biology

The pathway for polypeptides exported from E. coli includes the following steps, which occur in what order for correct export?

1.  A chaperone, SecA, binds to the polypeptide.

2.  A chaperone, SecB, binds to the polypeptide.

3.  ATP is hydrolyzed by Sec A.

4.  SecA pushes 20 amino acids of the polypeptide into the translocation complex.

#Question id: 4153

#Section 3: Genetics, Cellular and Molecular Biology

Ubiquitin-mediated protein degradation is a complex process, and many of the signals remain unknown.  One known signal involves recognition of amino acids in a processed protein that are either stabilizing (Ala, Gly, Met, Ser, etc.) or destabilizing (Arg, Asp, Leu, Lys, Phe, etc.), and are located at: