Termination signal

Codon Sequence of three nucleotides that codes for a single amino acid (or a termination signal)... 

The protein contains an N-terminal signal peptide of 17 amino acid residues for secretion. The luminescence reaction of coelenterazine catalyzed by the recombinant luciferase shows a luminescence emission maximum at 485 nm, whereas the luminescence catalyzed by the native luciferase shows a maximum at 480 nm. 

The DNA sequence analysis of specific genes has allowed the recognition of a number of sequences important in gene transcription. From the large number of bacterial genes smdied it is possible to construct consensus models of transcription initiation and termination signals. 

Rho-dependent transcription termination signals in E coll also appear to have a distinct consensus sequence, as shown in Figure 37—6. The conserved consensus sequence, which is about 40 nucleotide pairs in length, can be seen to contain a hyphenated or interrupted inverted repeat followed by a series of AT base pairs. As transcription proceeds through the hyphenated, inverted repeat, the generated transcript can form the intramolecular hairpin structure, also depicted in Figure 37-6. 

Figure 37-6. The predominant bacterial transcription termination signal contains an inverted, hyphenated repeat (the two boxed areas) followed by a stretch of AT base pairs (top figure). The inverted repeat, when transcribed into RNA, can generate the secondary structure in the RNA transcript shown at the bottom of the figure. Formation of this RNA hairpin causes RNA polymerase to pause and subsequently the p termination factor interacts with the paused polymerase and somehow induces chain termination.

The PelX protein contains 749 amino-acids including an amino-terminal signal sequence of 26 amino-adds. The celliilar localisation of the enzyme has not been rigorously determined. In E. chrysanthemi CUCPB1237, the exo-pectate lyase activity was cell-bound (14). The presence of this type of enzyme in the bacterial periplasm appeared normal since it acts better on oligomers produced by endo-pectate lyases than on long polymeric substrates (15). 

CBDA synthase shown to carry a highly similar N-terminal signal sequence to THCA synthase. It is thus suggested that this enzyme is localized... 

The murine stromal-derived factor-la (SDF-1)/CXCL12 was originally cloned from a cDNA library derived from the bone marrow stromal cell tine ST2 by a method to clone cDNAs that carry specific amino terminal signal sequences, such as those encoding intercellular signaling-transducing molecules... 

ALTERNATIVE START SITES If all of the above didn t provide enough diversity, some messages contain two AUG initiation codons separated by some intervening information. Protein synthesis can initiate at either site. This is useful for making proteins with or without NH2- terminal signal sequences. 

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