Consider the cyanobacteria Anabaena. Individual cells grow a…

Consider the cyanobacteria Anabaena. Individual cells grow attached to each other in long chains produced from binary fission. Most perform photosynthesis, using photosystems I and II to generate ATP and NADPH that they use to power the fixation of carbon dioxide via the Calvin cycle. However, a small number form heterocysts, cells that fix nitrogen into ammonium instead of performing photosynthesis. Heterocysts share their nitrogen compounds with their photosynthetic neighbors, who in turn share sugars with the heterocysts. If you extracted all the mRNA from a single heterocyst, and all the mRNA from a single photosynthetic cell, what information would this give you, i.e., what would this tell you about them?

Streptomyces rishiriensis is a Gram positive bacterium that…

Streptomyces rishiriensis is a Gram positive bacterium that produces dark melanin pigments and a number of antimicrobial compounds. You hope to find gene(s) responsible for the production of these melanin pigments. You transform a culture with a plasmid containing a transposon and a kanamycin resistance gene (kanR). Considering your transformation efficiency will be low, how might you find bacteria that have been successfully transformed?

Streptomyces rishiriensis is a Gram positive bacterium that…

Streptomyces rishiriensis is a Gram positive bacterium that produces dark melanin pigments and a number of antimicrobial compounds. You hope to find gene(s) responsible for the production of these melanin pigments. You transform a culture with a plasmid containing a transposon and a kanamycin resistance gene (kanR) and successfully isolate transformed mutants. You grow them in culture and spread them on the surface of multiple TSA plates. Following incubation, you observe mostly dark colonies along with an occasional clearish/white colony. What might best explain the presence of these clearish/white colonies?