Red Tides Trichodesmium erythraeum Microscopic view Present in

Red Tides

Trichodesmium erythraeum

Microscopic view § Present in the form of colonies § Responsible for increased nitrogen fixation in the presence of Iron.

Analysis of possible regulatory motifs § Fe 2+/Zn 2+ uptake regulation proteins (FUR) § Bacterioferritin ( cytochrome b 1) § ABC-type Fe 3+ transport system periplasmic component 9 known proteins known for iron regulation

Upstream Sequences of Iron regulatory proteins 1) Periplasmic protein upstream sequence 2) Bacterioferritin upstream sequence 3) FUR upstream sequence TTTTACTTCACGGGTCAAGATTTTTTCTCCCTTTTCTTCCTAAATTCGGACATTTTATCACTCCTTATAG CTTTTAACCCAAGATTGAGGTGATTTCCCTTTTTC A & T rich sequence What about similar genes in other organisms ?

Upstream sequences of orthologs with similar motifs Organism Gene Position Upstream Sequence Anabaena A 7120. all 1691 89 TCTTTCAAGAACTTCCTCAAGGCGAACACCTGAGTGCAGAAGATTTATAT Trichodesmium e. Tery. Te? 4228 32 TTTTTCAAAACCTGCCAAAAGGCAATCATCTGAGTGCCGAAGATCTTTAT Synechococcus e. S 7942. ser 2269 86 TCTTTCAAAATCTCCCAGCAGGTGAACACCTCAGTGCTGAGGACCTTTAC Anabaena v. A 29413. Av? 0480 89 TCTTTCAAGAACTTCCTCAAGGCGAACACCTGAGCGCAGAAGATTTATAT Nostoc p. S 6803. sll 0567 TTTTTCAAAATTTGCCGGAGGGGGAACATCTCAGTGCCGAGGAGTTACAC 89 Thermosynechococcus e. Te. BP 1. tll 0048 125 T T C C A G A A T C T G C C T A A G G G C A A T C A C C T G A G T G C T G A A G A C C T A C Crocosphaera w. Cwat. Cw? 5989 161 TACTTCATGCTCAACAAGTGGGAGAAATTTTGACTGGTTTAGAAGGCCAT Anabaena 161 TACTCCATGCTCAACAAGTAGGAGAAATTCTCACAGGTTTAGATGGACAT 161 TACTTCATGCCCAACAAGTGGGAGAAATTCTCACAGGATTAGATGGACAT A 7120. all 3940 Anabaena v. A 29413. Av? 3012 Crocosphaera w. Cwat. Cw? 4935 89 TC T T C C A A T C C C T A G G G A A T C A T T T G A G T G C T G A G G A A T T G T T T Nostoc p. 161 TACTTCATGCTGAACAAGTAGGAGAAATTCTTACCGGTTTAGATGGGCAT Trichodesmium e. Tery. Te? 3328 170 TACTTCATGCTCAACAAGCAGGAGAAATATTAACAGGTTTAGAAGGTCAT Gloeobacter v. TGTTCCAGGAGTTGCCGGAGGGCAATCACCTCAATGCCGAGGAGCTGCAC Npun. Np. F 6212 Gvi. glr 3304 98 Prochlorococcus m. PMED 4. PMM 0637 104 T A T T T G A A T T G G A G C A G G T A A T C A T T T A A G T G C G G A A G T T C A T

What can we conclude from the information ? § Matches with 2 Trichodesmium genes Already knew……… § Matches with 2 nostoc and 4 anabaena genes…… not a surprise…. . Both are rich in A and T nucleotides…… What are other matches ? . . . .

Other matches ? • • • Synechococcus e. Thermosynechococcus e. Crocosphaera w. (2 – Genes) Gloeobacter v. Prochlorococcus m. Iron regulatory upstream sequences somewhat similar to Trichodesmium……… Where else can we look for such matches ?

Finding FE+ regulatory genes ? § Intergenic sequences in the genome of Trichodesmium § Orthologs of the other promising iron regulatory genes in Trichodesmium.

Thanks To : Dr. Jeff Elhai Bioinformatics VCU Presented by : Sukalpa Dutta