According to the given information, the bacterial mRNA consists of about 800 nucleotides. Three consecutive nucleotides together make one genetic codon which in turn codes for one specific amino acid in the protein encoded by this mRNA.
So, an mRNA with 800 nucleotides will have total 800/3 = 266.67 or 266 genetic codes. The protein encoded by this mRNA would have a total of 266 amino acids.
Given that one amino acid imparts 110 units to the molecular weight of the protein, the protein with 266 amino acids have the molecular weight= 266 x 110 = 29260, that is about 30,000.
