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Vaccines based on proteins and peptides may be safer and if calculated based on many sequences, more broad-spectrum than those designed based on single strains. Physicochemical Property Consensus (PCPsubcon/sub) alphavirus (AV) antigens from the B-domain of the E2 envelope protein were designed, synthesized recombinantly and shown to be immunogenic (i.e. sera after inoculation detected the antigen in dotspots and ELISA). Antibodies in sera after inoculation with B-region antigens based on individual AV species (eastern or Venezuelan equine encephalitis (EEEVsubcon/sub, VEEVsubcon/sub), or chikungunya (CHIKVsubcon/sub) bound only their cognate protein, while those designed against multiple species (Mosaiksubcon/suband EVCsubcon/sub) recognized all three serotype specific antigens. The VEEVsubcon/suband EEEVsubcon/subsera only showed antiviral activity against their related strains (in plaque reduction neutralization assays (PRNTsub50/80/sub). Peptides designed to surface exposed areas of the E2-A-domain of CHIKVsubcon/subwere added to CHIKVsubcon/subinocula to provide anti-CHIKV antibodies. EVCsubcon/sub, based on three different alphavirus species, combined with E2-A-domain peptides from AllAVsubcon/sub, a PCPcon of 24 diverse AV, generated broad spectrum, antiviral antibodies against VEEV, EEEV and CHIKV, AV with less than 35% amino acid identity to each other (gt;65% diversity). This is a promising start to a molecularly defined vaccine against all AV. Further study with these antigens can illuminate what areas are most important for a robust immune response, resistant to mutations in rapidly evolving viruses. The validated computational methods can also be used to design broad spectrum antigens against many other pathogen families.

There is an urgent need for inexpensive, rapid and specific antigen-based assays to test for vaccine efficacy and detect infection with SARS-CoV-2 and its variants. We have identified a small, synthetic protein (JS7), representing a region of maximum variability within the receptor binding domain (RBD), which binds antibodies in sera from nine patients with PCR-verified COVID-19 of varying severity. Antibodies binding to either JS7 or the SARS-CoV-2 recombinant RBD, as well as those that disrupt binding between a fragment of the ACE2 receptor and the RBD, are proportional to disease severity and clinical outcome. Binding to JS7 was inhibited by linear peptides from the RBD interface with ACE2. Variants of JS7, such as E484 K or N501Y, can be quickly synthesized in a pure form in large quantities by automated methods. JS7 and related synthetic antigens can provide a basis for specific diagnostics for SARS-CoV-2 infections.

The synthesis of oligoethylene glycols of defined lengths possessing different end functionalities is described. The utility of these molecules towards the development of a generic membrane anchor is demonstrated.

Ion-exchange chromatography is a well-established method for the analysis and purification of phosphodiester-linked oligonucleotides. If elution is carried out under alkaline conditions, the secondary structure of G- and C-rich oligomers is disrupted. Furthermore, elution times become more sensitive to the G and T content of the oligomer, because G and T are deprotonated at pH 10. In recent work on peptide-nucleic acids (PNAs) we noted that mixtures of PNA oligomers G(sub 4), G(Sub 6), G(sub 8), and G(sub 10) are readily separated by elution at pH 12 on an RPC-5 column. Here we show that this separation method is more generally applicable.

The common nodulation genes of rhizobial bacteria code for enzymes involved in the synthesis of lipo-chitooligosaccharide signal molecules. These molecules not only trigger the development of nodules on the roots of leguminous plants, but similar signals may affect the growth and development of non-leguminous plants.

The d -xylan-degrading enzymes of Trichoderma lignorum can be induced by several oligo- and poly-saccharides. The induction is optimal when l -arabino- d -xylan is used as carbon source. The enzymes were also produced by cells grown on glycerol in the presence of 4-thioxylobiose (4-S-β- d -xylopyranosyl-4-thio- d -xylopyranose) and methyl β- d -xylopyranoside. These inducers were not taken up by the cells. The extent of induction was, however, lower than with xylobiose. Thioxylobiose was obtained in an overall yield of 55–60% from the reaction of 1,2,3-tri-O-benzoyl-4-O-trifluoromethylsulfonyl-β- l -arabinopyranose with the sodium salt of 1-thio-β- d -xylopyranose in N′,N″,N‴-hexamethylphosphoramide, followed by O-deacylation of the resulting 4-thiodisaccharide.

Hydroxyapatite chromatography has been used to separate all five isozymes of lactic dehydrogenase, six enzymatically active forms of bovine pancreatic DNase I, and a standard protein mixture. The proteins were eluted with a linear gradient of sodium phosphate. Enzyme activity recoveries were greater than 90%. Packing materials were obtained from commercial fine-particle-sized hydroxyapatite (DNA grade Bio-Gel HTP) by an elutriation procedure. Long columns packed with small crystals were run under low pressure at acceptable flow rates, and were used over prolonged periods.