Presented by: Emily Campbell PI: Dr. Stephen Giovannoni Mentor: Paul Carini Marine Microbiology Lab

 Discovered in 1990 by Stephen Giovannoni Most abundant heterotrophic organism in ocean surface waters world wide 1/3 of cells present in ocean surface water  Role of SAR11 Dissolved organic carbon cycling SAR11 oxidizes carbon → Releases CO 2  Ocean lacks large quantities of key nutrients CO 2 Organic Carbon AutotrophsHeterotrophs

 Most commonly found as phosphate (PO 4 )  An example of a nutrient found at low concentrations Below 5 nM  Required for all living things Nucleotides (DNA and RNA), phospholipids (cell membranes)  SAR11 thrives in low phosphate environments

 SAR11 isolate HTCC7211, HTCC1062, HTCC1002

 Hypothesis: Each SAR11 isolate can utilize different phosphorus compounds with varying abilities.  Prediction: If the isolate is able to utilize the given phosphorus-containing compound, we expect to observe maximum cell densities in excess of those cultures to which no phosphate has been added.

Negative ControlPositive ControlTest Compound Count Cells Plot Data

 2-aminoethylphosphate  cAMP  D-xylulose-phosphate  dATP  dCTP  dGTP  dTTP  D-Glucose 6 Phosphate  3-glycerophosphate  AMP  CMP  GMP  IMP  UMP  L-O Phosphoserine  Methylphosphate  Phosphite dibasic pentahydrate  Phosphoenol Pyruvate  Phosphonoacetic acid  Phytic Acid  D-ribose-5 phosphate  Sodium phosphite dibasic pentahydrate  Sodium Phosphonoformate  Sodium triphosphate  Uridine-5`- diphosphoglucose  DNA  RNA

 2-aminoethylphosphonic acid  dATP  dGTP  dCTP  dTTP  Deoxy-xylulose-phosphate  UMP  GMP  D-glucose 6 phosphate  3-glycerophosphate  Phosphoenol pyruvate  D-ribose-5 phosphate  Sodium phosphite dibasic pentahydrate  Sodium phosphonoformate HTCC 1062 HTCC 7211 HTCC 1002  2-aminoethylphosphonic acid  dGTP  dTTP  Deoxy-xylulose-phosphate  IMP  D-ribose-5 phosphate  Sodium phosphonoformate  Uridine 5’ diphosphoglucose  2-aminoethylphosphonic acid  dATP  dGTP  dCTP  dTTP  Deoxy-xylulose-phosphate  D-glucose 6 Phosphate  3-glycerophosphate  Methylphosphonic acid  Phosphoenol pyruvate  L-O Phosphoserine  D-ribose-5 phosphate  Sodium phosphite dibasic pentahydrate Shared between all three isolates Shared between HTCC1062 and HTCC7211 Shared between HTCC1062 and HTCC1002 Unique to that isolate

HTCC7211 HTCC1062 HTCC1002 IMP Uridine 5’ diphosphoglucose 2-aminoethylphosphonate dGTP dTTP D-xylulose-phosphate D-ribose-5 phosphate dATP dCTP D-glucose-6P 3-glycerophosphate PEP Phosphite Methylphosphonate L-O Phosphoserine UMP GMP Phosphonoformate

 Verify results Free phosphorus in stocks Test positive results in triplicate  What molecular pathways the compound could be used in What other necessities the phosphorus compound being transported could alleviate

Dr. Stephen Giovannoni Paul Carini HHMI Dr. Kevin Ahern