Based on the following DNA sequence comparisons, which two unidentified microorganisms would you conclude are most closely related? Choose one: A. Both microbial genomes include a gene that encodes for streptokinase, an enzyme and virulence factor that activates human plasminogen. B. Both microbial genomes include genes that encode for protein components of the prokaryotic ribosome. C. Both microbial genomes include genes that encode for photosynthetic photoreceptor proteins. D. Both microbial genomes include a gene that encodes for nitrogenase, a nitrogen-fixing enzyme.

Streptokinase (Ska) is a single-chain 414 amino acid protein, produced by certain Streptococci species (group A, C, and G streptococci), which possess an activity closer to two host proteins (urokinase-type and tissue-type plasminogen activators), as it non-enzymatically process inactive plasminogen to proteolytically active plasmin.

Streptokinase is a species-specific virulence factor. If both microbial genomes produces streptokinase, then these microorganisms can both be grouped as Streptococci since they are closely related.

All other choices do not certainly ease the relationship beyond the domain level.

eyitbay eyitbay · Answer 2 · 2020-02-05T11:53:16+01:00

Answer:

A. Both microbial genomes include a gene that encodes for streptokinase, an enzyme and virulence factor that activates human plasminogen.

Explanation:

Streptokinase is an enzyme (also synthesize as a medication) produced specifically by streptococci spp. If the two unidentified microbes could produce this enzyme, then they should contain the gene that codes for streptokinase .Thus they share certain genome characteristics, and are related.

Other options related the similarities to the domain levels only