Solar thermoelectric generator design and panel development program

Thermoelectric and mechanical performance of silicon-germanium solar thermoelectric generato

Biochemical and molecular characterization of the extracellular esterase from Streptomyces diastatochromogenes.

An esterase of Streptomyces diastatochromogenes was purified to homogeneity from culture filtrate. The purified enzyme had a molecular mass of 30,862 +/- 5.8 Da, as determined by electrospray mass spectrometry. The esterase-encoding gene was cloned on a 5.1-kb MboI fragment from S. diastatochromogenes genomic DNA into Streptomyces lividans TK23 by using plasmid vector pIJ702. Nucleotide sequence analysis predicted a 978-bp open reading frame, estA, encoding a protein of 326 amino acids, a potential ribosome binding site, and a putative 35- or 36-residue signal peptide for secretion in S. lividans or S. diastatochromogenes, respectively. The transcriptional initiation site was mapped 29 nucleotides upstream from the predicted translational start codon of estA in S. diastatochromogenes. The protein sequence deduced from the estA gene was similar to that of the esterase from the plant pathogen Streptomyces scabies. Both enzymes lacked the conserved motif GXSXG carrying the active-site serine of hydrolytic enzymes. A serine modified by [1,3-3H]diisopropyl fluorophosphate was located at position 11 of the mature enzyme in the sequence GDSYT. This finding and results obtained by site-directed mutagenesis studies indicate that serine 11 may be the active-site nucleophile

Peptide motifs of HLA-B51, -B52 and -B78 molecules, and implications for Behcet's disease

Here we report peptide motifs of five HLA-B molecules, B*5101, B*5102, B*5103 B*5201 and B*7801. Motifs were obtained by pool sequencing of natural ligands eluted from the respective molecules expressed in C1R cells upon transfection. A number of individual ligands that could be sequenced confirmed the motifs. All five HLA-B molecules belong to the HLA-B5, B35-cross-reactive group and are closely related as indicated by similar sequences. B51 and B52 are associated with Bw4, whereas B78 is associated with Bw6. One of the HLA-B molecules investigated here, HLA-B*5101, is associated with Behçet's disease, a multisystemic inflammatory disease affecting various organs. This disease is especially frequent among the Japanese population. The subtle differences between the peptide motifs of B*5101 as compared with the motifs of the four other closely related but not disease-associated molecules could shed light on the nature of the HLA-association of Behçet's disease

Analysis of a naturally occurring HLA class I-restricted viral epitope.

A previously described nonapeptide sequence motif for antigens recognized by T cells in the context of the human major histocompatibility complex (MHC) molecule HLA-A2.1 was used to identify the natural epitope of influenza A virus matrix protein. We show here that the peptide with the sequence GILGFVFTL is the synthetic analogue of the natural epitope by demonstrating the presence of the corresponding peptide on MHC molecules of virus-infected cells. The role of the hydrophobic anchor amino acids in positions 2 and 9, which constitute the epitope motif, was investigated with synthetic variants of the epitope and cytotoxic T lymphocytes as indicator cells. The crucial role of the side chains of amino acids in those positions was evidence by their influence on the efficiency of T-cell stimulation