NanoBio: Synechocystis

From OpenWetWare
Jump to navigationJump to search

Synechocystsis Primer

Introduction to Cyanobacteria

  • Cyanobacteria generate oxygen gas through oxygenic photosynthesis. Unlike purple sulfur bacteria or purple non-sulfur bacteria, cyanobacteria use chlorophyll a to gather light.
  • Cyanobacteria live close to the surface of ponds, and have two major absorption bands between 550-620 due to phycobiliproteins.

Synechocystis sp 6803 Genetics

  • Synechocystis carries multiple (6-12) copies of the genome in a single cell.
  • Synechocystis has about 3,260 genes that code for proteins.
  • Synechocystis is naturally transformable, i.e. it will uptake foreign DNA and incorporate this DNA into its genome by homologous recombination.

Synechocystis sp 6803 Growth

  • The doubling time of Synechocystis is 12 hours (versus 20 minutes for E. coli), and it takes 7-10 days to get visible colonies of transformants on a plate.
  • Liquid media: BG-11 media, Sigma catalog #, 500 mL of 50x ~$30
  • Light intensity: 50-70 umol photons m2/s
  • Temperature: 30-34 ºC
  • pH: 8-10

Synechocystis sp 6803 Metabolism

  • CO2 is assilimated through the Calvin cycle.
  • Not fully functional citric acid cycle.
  • Pentose phosphate is central pathway of carbohydrate metabolism.
  • Gram negative (double membrane).
  • Heterocysts form to fix nitrogen when NO3 and NH3 are absent.

Synechocystis sp 6803 Physiology

  • Synechocystis is typically a slightly oblong spheriod, approximately 1.5 microns in diameter.