Team:Heidelberg/Templates/Indigoidine week9

From 2013.igem.org

Revision as of 00:43, 5 October 2013

We want to assemble pKH1, which is a pSB1C3-derived plasmid containing pSB1C3-lacPromotor-BBa_B0034-bpsA(pMM64)-

BBa_B0034-svp(pMM65). Single fragments are amplified and cloned using a Gibson approach. We received Streptomyces lavendulae lavendulae DSMXXXX since S. lavendulae ATCC11924 has been shown to carry bpsA

[Takahashi 2007].

Fragment amplification for pKH1 (Konrad)

• prepare TB medium for ON (for comparement with LB)
• colony PCR for plated pMM64 and pMM65 strains from 2013-06-16
• prepare combinatorial experiment with gibson cloning or CPEC (polysytronic expression of bpsA and svp in TOP10)
• prepare primer for bpsA only plasmid for BAP1 validation

• 0.4 µl template
• 2x 5 µl Primer (1:10 dilution)
• 25 µl Phusion MM
• 14.6 µl H2O

• gel purification

f1: bpsA (all)

f2-6: single domains of bpsA and svp

f7: backbone

Assembly of pKH1 and Transformation (Konrad)

Gibson approach

• molecular ratio = backbone : inserts = 1 : 3
• partslength: bpsA=3.8 kbp; svp=0.8 kbp; pSB1C3=2.4 kbp

CPEC approach

Two different approaches were used. In the first approach 3 fragments (backbone (pSB1C3 based), bpsA and svp) were

used for assembly while for the second approach 4 different fragments (Backbone, AOxA, T-TE, svp) were used (like

for the Gibson mix). The amount of used template was calculated for backbone : insert ratio of 1:1 and for insert

fragment ratio at equimolar amount.

• 3 fragment mix
  • 3 µl template (f7:backbone)
  • 8 µl template (f1:bpsA)
  • 0.3 µl template (f6:svp)
  • 12.5 µl Phusion MM
  • 1.2 µl H2O

• 4 fragment mix
  • 3 µl template (f7:backbone)
  • 1.7 µl template (f2:AOxA)
  • 1.5 µl template (f5:T-TE)
  • 0.3 µl template (f6:svp)
  • 12.5 µl Phusion MM
  • 6 µl H2O

The used cycler program was carried out similar to CPEC paper for multipart assembly but I forgot to note down the

exact parameters. (Shame on me...)

Transformation

• into TOP10
• 4 plates (1:1 and 1:4 of Gibson mix; 1x of each CPEC mix)

Colony PCR

colony PCR of construct assembeled by Gibson; wanted amplicon size is around 1 kbp

analytical digestion of selected clones

validation of transformed BAP1 with Fussenegger plasmids

fusion PCR

Gibson Assembly of bpsA + svp insert

PCR for colony validation

IPTG induction, titration

IPTG induction, titration RESULT

Fussenegger plasmids in BAP1 under various conditions. BAP1 without any Plasmid, BAP1 transformed only with the bpsA carrying plasmid pMM64 and BAP1 transformed with the bpsA carrying plasmid pMM64 and svp carrying pMM65 were induced with four different IPTG concentration ranging from 100 µM to 10 mM at two different temperatures (18 °C and 24°C) for around 24 h.

CPEC and transformation

IPTG induction, titration RESULT

2 ml of samples from induction experiement from 2013-06-22 were centrifugated down and then visually compared. Like it can be seen, indigoidine is exported into the supernatant.

Streptomyces cultivation (Ralf)

media for streptomyces culture

• YEME medium (Kieser et al. 2000)
  • 10 g Glucose
  • 3 g Yeast extract
  • 5 g Bacteriological Peptone (I used Pankreatic Digest of Casein)
  • 3 g Malt Extract
  • 340 g Sucrose
  • ad 1 L water

• DSMZ medium 65 GYM streptomyces medium
  • 4 g Glucose
  • 4 g Yeast extract
  • 10 g Malt extract
  • (2 g CaCO3 for plates)
  • (12 g Agar for plates)
  • ad 1 L water

Results and Discussion

BAP1+pMM64+pMM65 eventually produced indigoidine. We will now focus on assembling our own constructs starting with

pKH1. Streptomyces cultures look like yeast and have a strong smell as in the forest.