Intro
What was the name of the multicellular bacterium investigated in the article?
Streptomyces coelicolor
How many Wild Type groups and Mutant groups did the study have?
12 total - 6 for each
What relationship(s) did the study find in general?
What is the advantage of division of labor?
Allows individuals to efficiently carry out functions that are mutually incompatible.
Clonal groups tend to have more cellular specialization and an increased likelihood of expressing the reproductive division of labor
How many transfers did they have with what type of methodological design?
25 transfers - Mutation Accumulation (MA) design
What were the findings from their study of genome deletion size?
- Positive correlation between size of genomic dleetions and amount of antibiotics produced
- Negative correlation between deletion size and spore production
The study intended to mimic the natural mode of .... when transferring spore-to-spore.
What is needed to meet the requirements of extreme altruism (or vice versa)?
High relatedness faciliates the extreme altrirums needed for reproductive sterility
What variables did the study measure in relation to the progression of transfers?
CFU (measure of fitness), MIC (susceptibility to other antibiotics), Deletion size (genomic deletion), Rate of mutation
What was the purpose of the Wild Type lineages?
Cotrol and comparative sample for mutant lineages
How does this experiment demonstrate kin selection?
At the cost of individual fitness (as shown in study), they continue to carry out this antibiotic-producing activity because it increases the overall fitness of the colony.
What are the characteristics of Streptomyces? (where do they live, what is their function, etc)
How frequent were the transfers in the study?
2 times / week (total 25 transfers)
What lineage of the mutants showed the most distinct impact by the transfers?
M2
What observations from the lineages over the 25 transfers resemble?
Mutational meltdown; accelerated fitness declines in caused by deletrious mutations
What was the hypothesis of the study?
Putatively altruistic cells (Streptomyce coelicolor) represent the sterile microbial caste due to their functional cohesiveness that arises due to their genome deletions. This is parallel to sterile insect workers or somatic cells that are differentiated to perform specialized tasks.
What genes are related to the phenotype: Arginine auxotrophy and Chloramphenicol susceptibility?
- argG(SCO7036)
- cmlR1 (SCO7526) and cmlR2 (SCO7662)
What did the study do after M2 lineage immediately went extinct after the 5th transfer?
W3 was treated as a mutant lineage from the 7th transfer. M2 was only evaluated for the first 2 time points.
What is a lingering issue that the study mentions?
Origin of mutant cells within growing colonies.