Lab Lore

This page is intended to serve as a centralized collection point for all those otherwise unwritten tips and tricks that we learn from more experienced labmates or from painful trial and error.

Red Food Coloring: Is it Fluorescent?

We added some red food coloring to all the dna we prepared for the iGEM 2007 part kits (1500 parts) to aid the process of visually confirming that 3uL had successfully been deposited in each well of each plate by our automation. Unfortunately, the presence of the dye seems to disrupt sequencing reactions.

Fluorometric analysis indicates the red food coloring fluoresces at 550 nm when illuminated with white light. The food coloring is from McCormick and the box is labeled Assorted Food Colors & Egg Dyes. The main ingredients are: Water, Propylene Glycol, FD&C Yellow 5, FD&C Red 40, FD&C Blue 1, FD&C Red 3, and 0.1% Propylparaben.

Lysostaphin is a Staphylococcus simulans metalloendopeptidase. It can function as an antimicrobial against Staphylococcus aureus. Lysostaphin is a 27 KDa glycylglycine endopeptidase, an antibacterial enzyme which is capable of cleaving the crosslinking pentaglycin bridges in the cell wall of Staphylococci.