Sodium Dodecyl Sulfate Lab Report

In this experiment Sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) was performed under reducing conditions to estimate the molecular weight of proteins within a sample. The protein sample was from the previous using anionic exchange chromatography to partially purify N-acetyl--D-hexosaminidase, Lab 3. The molecular weight was determined through the interpolation of a standard curve of proteins with a known molecular weight. The molecular weight of band 1 was determined to be 67,640 daltons and band 2 was 44,420 daltons, disproving the hypothesis that the molecular weight of the unknown protein sample was 28,000 daltons. The estimated molecular weight within this experiment for band 1 was close with literature values, which reported that under reducing condition the subunit molecular weights were approximately 63,000 and 56,000 daltons.

INTRODUCTION …show more content…
HEXA is the acid form of the enzyme consisting of a  subunit and HEXB is the basic form with two  subunits (1). The molecular weight (MW) of the native enzyme is 250,000 Da and the isozymic HEXA and HEXB forms have a MW of 223,000 Da. Subunit MW have values of approximately ~63,000 Da and ~56,000 Da (2). The pI of HEXA and HEXB are 5.4 and 7.9, respectively (3). This enzyme is found in the epididymis of the male reproduction tract and functions in the penetration of the zona pellucida for fertilization (4). SDS PAGE was implemented in this experiment to determine the approximate MW of the protein