For the vector construction, SQR gene was cloned into pSyn_6 vector, and through gel electrophoresis was checked the gene assembly. Figure 1 illustrates the bands of cloned pSyn_6 (5577 bp) in 1-4 wells between 3 and 4 ladder bands, which confirms the success of gene assembly. Also, cloned pSyn_6 plasmid was tested on a presence of SQR gene by PCR amplification using SQR primers. In Figure 2, we can see SQR bands (1271 bp) between 8 and 9 ladder bands that evidences of SQR presence in cloned pSyn_6 plasmid.

Figure 1.Agarose gel electrophoresis (1%) of cloned pSyn_6 plasmid with SQR (5577 bp).

Figure 2. Agarose gel electrophoresis (1%) of PCR amplified products using SQR primers to test its presence in cloned pSyn_6.

Transformation of S. elongatus PCC 7942 with SQR

After the gene construction, all attention was focused on transformation of cyanobacteria with SQR gene

Figure 3. Lamp with high light intensity.

Figure 4. Cyanobacteria colonies in BG-11 agar plates with spectinomycin.

Transformation verification

Confirmation of integration of the cloned pSyn_6 plasmid into genome was done by colony PCR amplification using SQR primers. In Figure 5, we can see colonies with inserted SQR genes, which were used to get liquid genetically modified cyanobacteria culture.