9-Fluorenylmethoxycarbonyl (Fmoc) amino acids were first used for solid phase peptide synthesis a little more than a decade ago. Since that time, Fmoc solid phase peptide synthesis methodology has been greatly enhanced by the introduction of a variety of solid supports, linkages, and side chain protecting groups, as well as by increased understanding of solvation conditions. These advances have led to many impressive syntheses, such as those of biologically active and isotopically labeled peptides and small proteins. The great variety of conditions under which Fmoc solid phase peptide synthesis may be carried out represents a truly "orthogonal" scheme, and thus offers many unique opportunities for bioorganic chemistry.

Solid phase peptide synthesis utilizing 9‐fluorenylmethoxycarbonyl amino acids

The study of effects of several parameters on silver staining of proteins has led to the development of a staining method which is simple and reliable, requires only few stable solutions, and can be applied to all gel types such as sodium dodecyl sulfate (SDS) containing polyacrylamide or isoelectric focusing gels. It can be used for ultrathin layers (0.1–0.2 mm) or thicker slab gels (up to 3 mm). With this method not only proteins but also polypeptides of molecular weights as low as 2500 are detectable with high sensitivity. Comparison of isoelectric focusing and SDS-containing gels and a simple spot test on thin gellayers show that the detection sensitivity depends not so much on the type of proteins but rather on their structure. The redox properties of the gel are important for the staining mechanism.

Simplified method for silver staining of proteins in polyacrylamide gels and the mechanism of silver staining

Species of RNA that bind with high affinity and specificity to the bronchodilator theophylline were identified by selection from an oligonucleotide library. One RNA molecule binds to theophylline with a dissociation constant Kd of 0.1 microM. This binding affinity is 10,000-fold greater than the RNA molecule's affinity for caffeine, which differs from theophylline only by a methyl group at nitrogen atom N-7. Analysis by nuclear magnetic resonance indicates that this RNA molecule undergoes a significant change in its conformation or dynamics upon theophylline binding. Binding studies of compounds chemically related to theophylline have revealed structural features required for the observed binding specificity. These results demonstrate the ability of RNA molecules to exhibit an extremely high degree of ligand recognition and discrimination.

http://science.sciencemag.org/content/sci/263/5152/1425.full.pdf

High-resolution molecular discrimination by RNA

Bordetella respiratory infections are common in people (B. pertussis) and in animals (B. bronchiseptica). During the last two decades, much has been learned about the virulence determinants, pathogenesis, and immunity of Bordetella. Clinically, the full spectrum of disease due to B. pertussis infection is now understood, and infections in adolescents and adults are recognized as the reservoir for cyclic outbreaks of disease. DTaP vaccines, which are less reactogenic than DTP vaccines, are now in general use in many developed countries, and it is expected that the expansion of their use to adolescents and adults will have a significant impact on reducing pertussis and perhaps decrease the circulation of B. pertussis. Future studies should seek to determine the cause of the unique cough which is associated with Bordetella respiratory infections. It is also hoped that data gathered from molecular Bordetella research will lead to a new generation of DTaP vaccines which provide greater efficacy than is provided by today's vaccines.

Molecular Pathogenesis, Epidemiology, and Clinical Manifestations of Respiratory Infections Due to Bordetella pertussis and Other Bordetella Subspecies

https://mmbr.asm.org/content/mmbr/56/4/622.full.pdf

Structure and function of cholera toxin and the related Escherichia coli heat-labile enterotoxin.

Pertussis toxin, a protein composed of five different subunits (S1, S2, S3, S4, and S5), is the major virulence factor of Bordetella pertussis. We have cloned and sequenced a DNA fragment of 4.7 kilobases that contains the genes coding for the five subunits. The genes are clustered within 3.2 kilobases in the following order: S1, S2, S4, S5, and S3. A sequence closely resembling Escherichia coli promoters is found only before the S1 gene, and a possible termination signal is present at the end of the S3 gene, which suggests that the pertussis toxin genes are organized in a single operon. A possible Shine-Dalgarno sequence is present before the S1 gene but not before the other four genes that 8-12 nucleotides upstream from the ATG codon show a new consensus sequence, 5'TCC(T)GG3', possibly involved in the regulation of translation. We have also found sequence homology between the S2 and S3 genes and their protein products indicating that gene duplication played a major role in the evolution of pertussis toxin.

https://www.pnas.org/content/pnas/83/13/4631.full.pdf

G. Antoni

Papers

Cloning and sequencing of the pertussis toxin genes: operon structure and gene duplication

SYNTHESIS OF ALPHA,BETA-POLY((2-HYDROXYETHYL)-DL-ASPARTAMIDE), a NEW PLASMA EXPANDER

A simple method for the estimation of amino groups on insoluble matrix beads.

Ultrasensitive silver-stain method for the detection of proteins in polyacrylamide gels and immunoprecipitates on agarose gels

Immunogenicity of a free synthetic peptide: carrier-conjugation enhances antibody affinity for the native protein.