Organo-metalloid detection in headspace gases 
    above bacteria
  Methods of Extraction
     Manual Gas Syringe (1mL)
     Solid Phase Micro Extraction (SPME)
  Instrumentation
     Gas Chromatography – F -induced 
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       Chemiluminescence Detection
     Gas Chromatography – Mass 
       Spectrometry
                                           
     Geobacillus stearothermophilus V
      Resistant to TeO -2 and TeO -2
                            3            4
      Growth Conditions of this thermophile
         Temperature:  60º C
         Aerobic Environment
      Difficult to perform headspace analysis.
         Oxidation of organo-sulfides and tellurides.
         Volatiles are purged out of the headspace.
                                         
      Genetic Modification of E. Coli JM109 Cells
       Open Reading Frames (ORF)
          ORF 600 – UbiE methyltransferase
          ORF 780 – uroporphyrin-III C-methyltransferase (cobA)
          ORF 399 – BtuR protein
       pSP72 cloning vector
          Plasmid is coded for ampicillin resistance.
          DNA was inserted at the HindIII restriction site.
                                            
    GC- SCD  Chromatogram of E. Coli 1VH 
    Headspace
                               
    Methanetellurol
     Was the chromatographic peak dimethyl selenide or 
       methanetellurol?
     If so, that means the tellurium amendments were 
       contaminated with selenium.
     Boiling Point of CH SeCH  - 54º C
                         3      3
     Boiling Point of CH TeH – 57º C
                         3