1 / 19

Stages of Sporulation in Bacillus subtilis

Stages of Sporulation in Bacillus subtilis. Germination. Stage 0. Stage II 1. Stage II 3. Stage III. Stage IV. Stage V. Stage VI. Stage VII. Asymmetric septation. Engulfment. Prespore protoplast. Cortex formation. Coat formation. Maturation. Release. Normal vegetative growth.

Audrey
Download Presentation

Stages of Sporulation in Bacillus subtilis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Stages of Sporulation in Bacillus subtilis Germination Stage 0 Stage II1 Stage II3 Stage III Stage IV Stage V Stage VI Stage VII Asymmetric septation Engulfment Prespore protoplast Cortexformation Coatformation Maturation Release Normal vegetative growth

  2. Stages of Sporulation in Bacillus subtilis How is the process regulated? Stage 0 Stage II1 Stage II3 Stage III Stage IV Stage V Stage VI Stage VII spo0 spoII spoIII spoIV spoV spoVI

  3. Stages of Sporulation in Bacillus subtilis Golden age of Bacillus genetics • Identify spo genes • Clone and characterize spo genes • Determine their interdependencies Stage 0 Stage II1 Stage II3 Stage III Stage IV Stage V Stage VI Stage VII spo0 spoII spoIII spoIV spoV spoVI

  4. Stages of Sporulation in Bacillus subtilis Errington and Mandelstam (1986) • Care in using reporter gene (lacZ) • How is regulation exerted? • Dependence of spoIIA expression on other genes Stage 0 Stage II1 Stage II3 Stage III Stage IV Stage V Stage VI Stage VII spo0 spoII spoIII spoIV spoV spoVI spoIIA

  5. Goals of Errington and Mandelstam Measure spoIIA expression: wt vs spo mutants spoIIAA spoIIAB spoIIAC lacZ Psp spoIIA Psp spoIIA::lacZ ß-galactosidase

  6. Psp spoIIA::lacZ Goals of Errington and Mandelstam Measure spoIIA expression: wt vs spo mutants B. subtilis wild type spoIIA::lacZ B. subtilis spo0A43 B. subtilis spo0B136 B. subtilis spo0D8 B. subtilis spoIIAA562 B. subtilis spoIIB131 B. subtilis spoIID298 Need a way to move around spoIIA::lacZ B. subtilis spoIIIA65 B. subtilis spoIIIB2 B. subtilis spoIIIC94 B. subtilis spoIVA67 B. subtilis spoIVB165 B. subtilis spoIVC23 B. subtilis spoVA89 B. subtilis spoVB91 B. subtilis spoVC134 B. subtilis spoVIA513 B. subtilis spoVIB520 B. subtilis spoVIC610 B. subtilis gerE36 . . .

  7. Psp spoIIA::lacZ Goals of Errington and Mandelstam Make spoIIA::lacZ transportable 105J19 cat 105J19 105J19: temperate phage Infection Lysogeny Lysis

  8. 105J19 cat 105J19 Psp spoIIA::lacZ Goals of Errington and Mandelstam Make spoIIA::lacZ transportable recombination Wt (105J19)lysogen Wt (105J19 spoIIAA::lac-cat) Transducing phage Select for Cmr . . . spo-lysogen spo-lysogen spo-lysogen spo-lysogen

  9. NO2 NO2 HO OH OH OH OH O O O OH OH OH OH OH Goals of Errington and Mandelstam Measure expression from spoIIA::lacZ Starve cells Break cells + ONPG ß-gal Conclusion?

  10. OH OH OH OH O O O OH OH OH OH OH Goals of Errington and Mandelstam Measure expression from spoIIA::lacZ Starve cells Break cells + MUG ß-gal MUG Moral Beware of equating what is measured with what is sought

  11. Induction of spoIIA::lacZ during sporulation (Figure 2a) wt spoIIA::lacZ ß gal activity(ONPG) wt 0 h 6 h Time after move to starvation medium

  12. Induction of spoIIA::lacZ during sporulation (Figure 2b) wt spoIIA::lacZ spoIIA- ß gal activity(MUG) wt spoIIA::lacZ spoIIA+ wt 0 h 6 h Time after move to starvation medium Moral Beware of side effects. Context is important.

  13. Psp Why does spoIIA::lacZ expression fall? Cm RNA secondary structure transcription translation proteindegradation RNAdegradation Transcriptionalregulators Not well understood Presence of proteases

  14. Why does spoIIA::lacZ expression fall? (Figure 3) +Cm +Cm +Cm ß gal activity(MUG) +Cm 0 h 3 h Time after move to starvation medium Rate of protein degradation constant

  15. Psp Why does spoIIA::lacZ expression fall? transcription translation proteindegradation RNAdegradation RNA MUG Time after starvation

  16. Why controls spoIIA::lacZ expression? Table 2 Spo0proteins SpoIIproteins SpoIIIproteins SpoIVproteins SpoVproteins

  17. Why controls spoIIA::lacZ expression? Table 2 Spo0proteins SpoIIproteins SpoIIIproteins SpoIVproteins SpoVproteins Nonregulatory protein Nonregulatory protein Nonregulatory protein Nonregulatory protein Nonregulatory protein 1. How does this work? Hint: Spo0AA is a sigma factor

  18. Why controls spoIIA::lacZ expression? Table 2 Spo0proteins SpoIIproteins SpoIIIproteins SpoIVproteins SpoVproteins 1. How does it get started? Environmental sensing + signal transduction

More Related