• Publications
  • Influence
Algae acquire vitamin B12 through a symbiotic relationship with bacteria
It is shown that the role of vitamin B12 in algal metabolism is primarily as a cofactor for vitamin B 12-dependent methionine synthase, and that cobalamin auxotrophy has arisen numerous times throughout evolution, probably owing to the loss of theitamin B12-independent form of the enzyme. Expand
Microbial production of vitamin B12
The rich scientific history of vitamin B12 research, its biological functions and the pathways employed by bacteria for its de novo synthesis are described, and current strategies for the improvement ofitamin B12 production using modern biotechnological techniques are outlined. Expand
Algae Need Their Vitamins
Algae are simple photosynthetic eukaryotes which—owing to their colonization of the oceans—are responsible for up to 50% of the planet's atmospheric carbon fixation ([22][1]). They comprise a diverseExpand
A mutation in guanylate cyclase activator 1A (GUCA1A) in an autosomal dominant cone dystrophy pedigree mapping to a new locus on chromosome 6p21.1.
It is proposed that a single base pair missense mutation at codon 99 in exon 2 of this gene generating a tyrosine-to-cysteine change would at least disrupt the EF3handof GCAP1 thereby preventing calcium binding and consequently interfere with activation, and could explain the ultimate demise of cone photoreceptor cells. Expand
Synthesis of empty bacterial microcompartments, directed organelle protein incorporation, and evidence of filament-associated organelle movement.
It is demonstrated that the shell of the metabolosome (representing an empty BMC) can be produced within E. coli cells by the coordinated expression of genes encoding structural proteins. Expand
Cyanobacteria and Eukaryotic Algae Use Different Chemical Variants of Vitamin B12
It is shown that the abundant marine cyanobacterium Synechococcus synthesizes only pseudocobalamin, in which the lower axial ligand is adenine, indicating that the two major phytoplankton groups use a different B12 currency. Expand
Biochemical and Structural Insights into Bacterial Organelle Form and Biogenesis*
It is shown that the 21 gene regulon specifying the pdu organelle and propanediol utilization enzymes from Citrobacter freundii is fully functional when cloned in Escherichia coli, both producing metabolosomes and allowing propanedol utilization. Expand
Mutualistic interactions between vitamin B12 -dependent algae and heterotrophic bacteria exhibit regulation.
A system to study the interaction between algae and heterotrophic bacteria at the molecular level and the implications for the widespread distribution of cobalamin auxotrophy in the algal kingdom are established. Expand