FSHN 440 - Assignment 1 PDF

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FSHN 440 UH Manoa - ASSIGNMENT 1...

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1. Template strand = 3’ -CTA TGC CGA ATG-5’ a. Sequence of the coding strand:  GAT ACG GCT TAC b. Sequence for mRNA transcribed:  GAU ACG GCU UAC c. Sequence of amino acids in the polypeptide coded for by the transcribed mRNA:    

GAU ACG GCU UAC

= Aspartic acid = Threonine = Alanine = Tyrosine

d. Anticodon sequences of 4 tRNA molecules involved in the translation:  CUA, UGC, CGA, AUG e. Different mRNA strand that can be used to synthesize the same polypeptide:    

GAC = Aspartic acid ACU = Threonine GCA = Alanine UAU = Tyrosine

2. Based on the composition of ribosome, central dogma, and bacterial cell division, bacteria cells make their ribosomes by: Ribosomes are made out of rRNA, ribosomes, and proteins. Ribosomes are composed of special proteins and nucleic acids. According to the central dogma, which is the pathway from DNA to RNA and RNA to protein, ribosomes are formed during the transcription process. Transcription is the first step in decoding a cell's genetic information. During transcription, enzymes called RNA polymerases build RNA molecules. Three general classes of RNA molecules are involved in expressing the genes encoded within a cell's DNA. Messenger RNA (mRNA) molecules carry the coding sequences for protein synthesis and are called transcripts; ribosomal RNA (rRNA) molecules form the core of a cell's ribosomes (the structures in which protein synthesis takes place); and transfer RNA (tRNA) molecules carry amino acids to the ribosomes during protein synthesis.

Although only a few rRNA molecules are present in each ribosome, these molecules make up about half of the ribosomal mass. The remaining mass consists of a number of proteins — nearly 60 in prokaryotic cells and over 80 in eukaryotic cells. During translation, these tRNAs carry amino acids to the ribosome and join with their complementary codons. Then, the assembled amino acids are joined together as the ribosome, with its resident rRNAs, moves along the mRNA molecule in a ratchet-like motion Based on bacteria cell division, when the cell is divided into two, four, and so on, both of the cells get half of the cell content from the parent, which consist of ribosomes and cytoplasm. The rRNA (ribosomal RNA) subunits of the prokaryotic ribosome (5S, 16S and 23S) are processed from a larger pre-rRNA gene. The pre-rRNA gene is transcribed by a large specialized enzyme called RNAP or RNA polymerase. The transcribed pre-rRNA sequence is then processed further into the 5S, 16S and 23S rRNA sub-units by ribonuclease enzymes. The second component of the ribosmes - the ribosomal proteins, or r proteins - are expressed from a separate gene and then bind with the rRNA sub units to form a mature ribosome....