Diazocyte development in the marine diazotrophic cyanobacterium Trichodesmium

• DOI: 10.1099/mic.0.051268-0
• Publication Date: 2011-11-04T05:07:15Z
• Authors: Gustaf Sandh; Linghua Xu; Birgitta Bergman
• Keywords: Trichodesmium; Trichome

The establishment of non-diazotrophic cultures the filamentous marine cyanobacterium Trichodesmium erythraeum IMS101 enabled first detailed investigation process leading to development its unique nitrogen-fixing cell type, diazocyte. Trichome heterogeneity was apparent already within 3–8 h, while differentiation mature diazocytes, containing nitrogenase enzyme, required 27 h after removal combined nitrogen. distribution 'pro-diazocytes' trichomes correlates with localization which suggests that pattern regulation is an early event during diazocyte development. initially identified as changes in subcellular ultrastructure, most notably degradation glycogen granules and gas vacuoles. These were preceded by induced expression global nitrogen regulator ntcA at stage deprivation, followed elevated genes related metabolism their corresponding proteins. strongest induction (10-fold) transcription respiratory gene coxB2, stage, important role for respiration subsequent energy generation found, creation reducing environment fixation diazocytes.