Using simple design and selective pressure, we have evolved an artificial M13 bacteriophage coat protein. M13 coat proteins first reside in the bacterial inner membrane and subsequently surround the DNA core of the assembled virus. The artificial coat protein (ACP) was designed and evolved to mimic both functions of the natural M13 coat proteins, but with an inverted orientation. ACP is a non-f...

The amino acid sequence of a polypeptide defines both the folding pathway and the final three-dimensional structure of a protein. Eighteen amino acid substitutions have been identified in bacteriophage P22 coat protein that are defective in folding and cause their folding intermediates to be substrates for GroEL and GroES. These temperature-sensitive folding (tsf) substitutions identify amino a...

Tomato ringspot nepovirus (TomRSV) produces a 45 kDa movement protein and a 58 kDa coat protein in infected plants. Accumulation of the movement protein in relation to that of the coat protein was studied in infected protoplasts using a monoclonal antibody against the movement protein and polyclonal antibodies against the coat protein. Unlike most other viral movement proteins, the TomRSV movem...

Turnip Yellow Mosaic Virus RNA directs the synthesis in vitro of its coat protein in a wheat germ cell-free extract. Optimum conditions for synthesis have been defined, and the effect of spermine on specifically enhancing coat protein formation has been examined. Identity between the in vitro synthesized coat protein and authentic coat protein of Turnip Yellow Mosaic Virus was established by an...

Alterations in the structure of the tobacco mosaic virus (TMV) coat protein affect the elicitation of the N' gene hypersensitive response (HR) in Nicotiana sylvestris. To investigate this structure-function relationship, amino acid substitutions with predicted structural effects were created throughout the known structure of the TMV coat protein. Substitutions that resulted in the elicitation o...

Crystalline arrays of proteinaceous subunits forming surface layers (S-layers) are now recognized as one of the most common outermost cell envelope components of prokaryotic organisms. The surface layer protein of Lactobacillus acidophilus ATCC4356 is composed of a single species of protein of apparent molecular weight of 43-46 KDa. Considering the Lactobacillus acidophilus ATCC4356 having the ...

Many viruses encode scaffolding and coat proteins that co-assemble to form procapsids, which are transient precursor structures leading to progeny virions. In bacteriophage P22, the association of scaffolding and coat proteins is mediated mainly by ionic interactions. The coat protein-binding domain of scaffolding protein is a helix turn helix structure near the C terminus with a high number of...

The R17/MS2 coat protein serves as a translational repressor of replicase by binding to a 19 nt RNA hairpin containing the Shine-Dalgarno sequence and the initiation codon of the replicase gene. We have explored the structural features of the RNA operator site that are necessary for efficient translational repression by the R17/MS2 coat protein in vivo . The R17/MS2 coat protein efficiently dir...

Assembly of certain classes of bacterial and animal viruses requires the transient presence of molecules known as scaffolding proteins, which are essential for the assembly of the precursor procapsid. To assemble a procapsid of the proper size, each viral coat subunit must adopt the correct quasiequivalent conformation from several possible choices, depending upon the T number of the capsid. In...

From in vitro protein synthesis studies and nucleotide sequence analysis it has been deduced that, unlike the major coat proteins of the hitherto studied filamentous bacterial viruses Ff (M13, fd and f1), IKe and Pf1, the major coat protein of the filamentous Pseudomonas aeruginosa virus Pf3 is not synthesized as a precursor containing a leader signal polypeptide at its N-terminal end. From the...