Protein in prokaryotes

Controlled expression of genes coding for biologically active proteins in prokaryotes and eukaryotes, including transformed mammahan cells... 

The most striking difference between DNA-binding proteins in prokaryotes and eukaryotes has to do with the symmetry of the interaction. In prokaryotes the binding proteins almost always interact in a symmetrical fashion with the DNA. In eukaryotes most of the cases that have been examined so far involve proteins that interact in an asymmetrical fashion with the DNA. In many cases the regulatory proteins interact in multisubunit complexes that contain nonidentical subunits. Four different types of structural motifs are discussed The homeodomain, the zinc finger, the leucine zipper, and the helix-loop-helix. 

In eukaryotes, each mRNA is monocistronic, that is, discounting any subsequent post-translational cleavage reactions that may occur, the mRNA encodes a single protein. In prokaryotes, many mRNAs are polycistronic, that is they encode several proteins. Each coding sequence in a prokaryotic mRNA has its own initiation and termination codons. 

Park KS, Jang YS, Lee H, Kim JS (2005) Phenotypic alteration and target gene identification using combinatorial libraries of zinc finger proteins in prokaryotic cells. J Bacteriol 187 5496-5499... 

Controlled expression of gene coding biologically active proteins in prokaryots and eukaryots including transformed mcunmal cells, hybridoma and monoclonal antibody methods. 

An interesting example of negative translational regulation in prokaryotes is provided by ribosomal protein synthesis. The approximately 55 proteins in prokaryotic ribosomes are coded for by genes located in 20 operons. Efficient bacterial growth... 

Expression of proteins in prokaryotes and eukaryotes cells Hybridoma and monoclonal antibody methods... 

Most of the DNA in eukaryotic cells is located in the nucleus, extensively folded Into the familiar structures we know as chromosomes (Chapter 10). Each chromosome contains a single linear DNA molecule associated with certain proteins. In prokaryotic cells, most or all of the genetic Information resides... 

In the genetic code, methionine is coded for by the codon AUG. This codon is called the start codon because methionine is the first amino acid used to build a protein chain. Methionine forms the so-called amino terminus of a protein. In prokaryotes, a modified form of methionine, formyl-methionine is used as the first (but not subsequent) amino acid in proteins. Formyl-methionine is carried by a modified tRNA from the tRNA that carries unmodified methionine. 

Wurgler-Murphy S M, King D M, Kennelly P J (2004). The Phosphorylation Site Database A guide to the serine-, threonine-, and/or tyrosine-phosphorylated proteins in prokaryotic organisms. Proteomics. 4 1562-1570. 

CheY apparently belongs to a superfamily of structurally similar proteins in prokaryotes [38, 755]. In addition, it has a significant sequence homology and three-dimensional structural similarity to the eukaryotic CTP-binding protein Ras p21 [152], as well as a three-dimensional structural resemblance to the superfamily of hydrolases, which consists of P-type ATPases, phosphatases, and more [601]. 

In 2005, using a combinatorial library prepared by Ugi condensation, the same group reported an artificial metalloprotease-type catalyst (19 mol%) that selectively hydrolyzed a disease-related enzyme, peptide deformylase (PDF), at the GInl52-Argl53 bond (Fig. 15) [94]. This enzyme is involved in deformylation of proteins in prokaryotic translational systems. The optimal proteolytic activity was produced at pH 7.5. A docking simulation study predicted preferential interaction of PDF with the (S)-enantiomer complex, and hydrogen bonding and van der Waals interactions between the complex with specific amino acid residues near the scissile peptide bond. 

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