Category:Team Green B

Figure 1

Sequence similarity with protein typically expressed in E. coli that is known to have this activity. "The enzyme reaction shows an ordered binding mechanism where the magnesium ion complex of 5-phosphoribosyl-1-pyrophosphate binds first followed by quinolinic acid. The products are pyrophosphate, CO2, and nicotinate mononucleotide."

The nadC gene from Escherichia coli was isolated and sequenced. The gene was then cloned into an expression vector and, following transformation, the resulting bacteria were able to produce quinolinate phosphoribosyl transferase as about 2% of the soluble protein. The enzyme was purified in five steps leading to a homogeneous preparation. The enzyme reaction shows an ordered binding mechanism where the magnesium ion complex of 5-phosphoribosyl-1-pyrophosphate binds first followed by quinolinic acid. The products are pyrophosphate, CO2, and nicotinate mononucleotide.

MltA is a lytic transglycosylase of Gram-negative bacteria that cleaves the beta-1,4 glycosidic linkages between N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) in peptidoglycan. Since these sites have determined the crystal structures of MltA from Neisseria gonorrhoeae and Escherichia coli (NgMltA and EcMltA), which have only 21.5% sequence identity but have 2 main domains separated by a deep grove pointing that they are both MltA proteins, we can conclude that this protein in Bacillus phage TsarBomba is also a MltA protein with the same protein function.

MltA is a lytic transglycosylase of Gram-negative bacteria that cleaves the beta-1,4 glycosidic linkages between N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) in peptidoglycan. We have determined the crystal structures of MltA from Neisseria gonorrhoeae and Escherichia coli (NgMltA and EcMltA), which have only 21.5% sequence identity but have 2 main domains separated by a deep grove pointing that they are both MltA proteins.

This protein is distantly homologous to the Escherichia coli ribonucleotide reductase, and this is inferred from blastp hits from query TsarBomba to the E coli phage Lw1, with 24% identity, and a 2e-14 e value.

"The R166Q mutant was crystallized in the presence of dUMP and a structure determined to 2.9 A resolution, but neither the ligand nor the sulfate from the crystallization buffer was found in the active site." meaning that this protein has a TS sight and if this site was mutated from a R to a Q at the 166 peptide, the site was inactive. This has a similar sequence from the TS in E.coli.

Fig 2

BlastP shows e-values of 3e-140 or less depicting sequence similarity to Bacillus phage Moonbeam and Spock which have been identified to have DNA primase gene products. Moonbeam and Spock have homologous sequences for this gene therefore it can be assumed that the protein encoded by TsarBomba will have a similar enzymatic function

BlastP shows that the protein is a homolog of phosphoadenosine phosphosulfate reductase (WP_001466333.1 coded by E.coli). The conserved binding domains and sequence similarity provide support for the claim that this protein provides reductase enzymatic activity