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A lectin was isolated from the fruiting bodies of Ischnoderma resinosus using affinity chromatography on Sepharose 4B. This lectin is composed of two identical subunits of 16 kDa. It exhibits specificity towards β-galactosyl residues.

Secondary structure is not typically observed for small peptides in solution. Several of the properties of alpha-helical peptides are known which lead to the stabilization of the structure. The utilization of all the known factors important for alpha-helical stabilization in the design of model alpha-helical peptides (MAP) is reported. The peptides are based on the repeating eleven amino acid sequence, Glu-Leu-Leu-Glu-Lys-Leu-Leu-Glu-Lys-Leu-Lys (MAP1-11). The CD spectra of these peptides give evidence for more alpha-helical content than has been reported for any short peptide (less than 18 amino acids) to date. This alpha-helical tendency does not require the presence of lipid or reduced temperature. For instance, Suc-[Trp9]MAP9-3'' amide (5), a seventeen amino acid peptide has 100% and 80% alpha-helical contents at 1.7 x 10(-4) M and 1.7 x 10(-5) M, respectively. Suc-[Trp9]MAP2-11 amide (3), merely ten amino acids in length, is 51% alpha-helical at 1.7 x 10(-4) M in 0.1 M phosphate buffer at room temperature. In the presence of lipid or trifluoroethanol, the alpha-helical content of these peptides is increased. This series of peptides demonstrates the complimentarity of various secondary structure design principles and the extent to which structure can be induced in small linear peptides.

The ubiquitin–proteasome system is known to be utilized by coxsackievirus to facilitate its propagation within the host cells. The present study explores the role of tripeptidyl peptidase II (TPPII), a serine peptidase contributing to protein turnover by acting downstream of the proteasome, in regulating coxsackievirus infection. Inhibition of TPPII does not affect virus replication in cells with functional proteasome. However, when the proteasome is impaired, TPPII appears to serve as an alternative to maintain low levels of virus infection. Our results suggest an important function of TPPII in the maintenance of viral growth and may have implications for anti-viral therapy.

2.1. Preparation of tissue Rats, about one month old, were killed by a blow on the neck. Brains were removed, and cortices were carefully cleaned of white matter. The cortices were washed in Krebs-Ringer phosphate buffer to remove blood cells, and placed on a large watch-glass filled with 5 ml of Krebs-Ringer phosphate buffer, pH 7.4, containing 10 mM glucose. 0.02% collagenase, chromatographically purified (Worthington), 0.1% hyaluronidase, type I (Sigma) and 1% BSA were added, and the tissue was torn in small pieces with two forceps. The solution obtained was poured into a glass vessel for incubation at 37” in an atmosphere of 100% 0, for 60 min, with constant shaking. At the end of the incubation the resulting tissue suspension was poured into a bag of nylon mesh, pore size 500 pm, placed inside a glass vessel (nylon bags were shaped by a hot iron). The vessel was mounted on a ball vibrator (Westin and Backlund, Stockholm) suspended freely in air by its gas hose and shaken at a high frequency for 5 min, constantly moving the nylon bag

Antibodies were elicited against chromatographically purified histone H l subfractions or against their complexes with RNA and their specificity studied by enzyme-linked immunosorbent assay. The results show that complexing of the pure protein with RNA (i) does not lead to any significant increase in the antibody titer and (ii) results in obtaining antibodies predominantly against the common antigenic determinants present in the HI histone class. On the other hand, using pure histone fractions for immunization gives rise to antibody populations reacting mainly with the subfraction-specific determinants on the histone molecule. In view of these results the literature data should be interpreted with caution.

Aglycosylated IgG produced by hybridoma cells cultured in the presence of tunicamycin was compared with normal IgG for its ability to bind to staphylococcal protein A. No differences were found in binding or elution profiles. It is concluded that aglycosylation does not produce major structural alterations at the CH2CH3 interface of the Fc region of IgG.