A high confidence, manually validated human blood plasma protein reference set.

Background: The immense diagnostic potential of human plasma has prompted great interest and effort in cataloging its contents, exemplified by the Human Proteome Organization (HUPO) Plasma Proteome Project (PPP) pilot project. Due to challenges in obtaining a reliable blood plasma protein list, HUPO later re-analysed their own original dataset with a more stringent statistical treatment that resulted in a much reduced list of high confidence (at least 95%) proteins compared with their original findings. In order to facilitate the discovery of novel biomarkers in the future and to realize the full diagnostic potential of blood plasma, we feel that there is still a need for an ultra-high confidence reference list (at least 99% confidence) of blood plasma proteins.

FliL is a membrane-associated component of the flagellar basal body of Salmonella.

FliL is one of the least understood proteins in the flagellar systems of Salmonella and Escherichia coli. There is no apparent mutant phenotype associated with it, even when virtually the entire coding sequence has been eliminated. In this study it has been shown that FliL is a cytoplasmic membrane protein associated with the basal body.

A comparison of viral immune escape strategies targeting the MHC class I assembly pathway.

Peptide fragments from proteins of intracellular pathogens such as viruses are displayed at the cell surface by MHC class I molecules thus enabling surveillance by cytotoxic T cells. Peptides are produced in the cytosol by proteasomal degradation and translocated into the endoplasmic reticulum by the peptide transporter TAP. Empty MHC class I molecules associate with TAP prior to their acquisition of peptides, a process which is assisted and controlled by a series of chaperones.

Interaction of murine MHC class I molecules with tapasin and TAP enhances peptide loading and involves the heavy chain alpha3 domain.

In human cells the association of MHC class I molecules with TAP is thought to be mediated by a third protein termed tapasin. We now show that tapasin is present in murine TAP-class I complexes as well. Furthermore, we demonstrate that a mutant H-2Dd molecule that does not interact with TAP due to a Glu to Lys mutation at residue 222 of the H chain (Dd(E222K)) also fails to bind to tapasin.

Retention of empty MHC class I molecules by tapasin is essential to reconstitute antigen presentation in invertebrate cells.

Presentation of antigen-derived peptides by major histocompatibility complex (MHC) class I molecules is dependent on an endoplasmic reticulum (ER) resident glycoprotein, tapasin, which mediates their interaction with the transporter associated with antigen processing (TAP). Independently of TAP, tapasin was required for the presentation of peptides targeted to the ER by signal sequences in MHC class I-transfected insect cells. Tapasin increased MHC class I peptide loading by retaining empty but not peptide-containing MHC class I molecules in the ER.

Sequence, linkage to H2-K, and function of mouse tapasin in MHC class I assembly.

Assembly of major histocompatibility complex (MHC) class I molecules in human cells is dependent on the accessory protein tapasin, which mediates their interaction with the transporters associated with antigen processing (TAP) and thereby ensures efficient peptide binding. Analysis of a mouse tapasin complementary DNA defined a conserved polypeptide sharing sequences diagnostic of a transmembrane protein related to the immunoglobulin superfamily, and an endoplasmic reticulum retention motif. The mouse tapasin gene was mapped about 70 kilobases from H2-K at the centromeric end of the mouse MHC.

Primary intracerebellar osteosarcoma arising within an epidermoid cyst.

The authors report a case of a primary extraskeletal osteosarcoma arising within an epidermoid cyst in the parenchyma of the cerebellum in a 64-year-old woman. On initial presentation, the tumor involved the midline cerebellum without attachment to the surrounding dura mater or calvarium. Complete medical and radiologic evaluation failed to reveal a primary skeletal or other extraskeletal osteosarcoma.

Translation of the flagellar gene fliO of Salmonella typhimurium from putative tandem starts.

The flagellar gene fliO of Salmonella typhimurium can be translated from an AUG codon that overlaps the termination codon of fliN (K. Ohnishi et al., J.

The FliO, FliP, FliQ, and FliR proteins of Salmonella typhimurium: putative components for flagellar assembly.

The flagellar genes fliO, fliP, fliQ, and fliR of Salmonella typhimurium are contiguous within the fliLMNOPQR operon. They are needed for flagellation but do not encode any known structural or regulatory components. They may be involved in flagellar protein export, which proceeds by a type III export pathway.

Physiological and biochemical analyses of FlgH, a lipoprotein forming the outer membrane L ring of the flagellar basal body of Salmonella typhimurium.

The FlgH protein of Salmonella typhimurium, from which the outer membrane L ring of the flagellar basal body is constructed, has a consensus motif (LTG C) for lipoylation and signal peptide cleavage. We have confirmed the previous finding (M. Homma, K.

Comparative analysis of flagellin sequences from Escherichia coli strains possessing serologically distinct flagellar filaments with a shared complex surface pattern.

Escherichia coli morphotype E flagellar filaments have a characteristic surface pattern of short-pitch loops when examined by electron microscopy. Seven of the 50 known E. coli H (flagellar antigen) serotypes (H1, H7, H12, H23, H45, H49, and H51) produce morphotype E filaments.

Monoclonal antibodies against serotype specific and conserved epitopes in morphotype E Escherichia coli flagellins.

Monoclonal antibodies (mAbs) were used to examine the interrelationships between morphologically identical flagellar filaments from Escherichia coli H serotype strains belonging to morphotype E. Serotype specific mAbs recognised epitopes exposed on the surface of flagellar filaments from H1, H7, H23, H49 and H51, but were inaccessible to immunolabelling in H45. Several mAbs which recognised conserved epitopes were also examined.

A high-molecular-weight fraction of smooth lipopolysaccharide in Klebsiella serotype O1:K20 contains a unique O-antigen epitope and determines resistance to nonspecific serum killing.

The lipopolysaccharide (LPS) O-antigen side chains of Klebsiella serotype O1 have been studied by using mutants selected by resistance to a Klebsiella bacteriophage designated O1-A. Two classes of LPS mutants were identified. The major group (90%) synthesized rough LPS.

Mutants of Escherichia coli O9:K30 with altered synthesis and expression of the capsular K30 antigen.

Escherichia coli K30 produces a thermostable group I capsular polysaccharide. Two classes of mutants were isolated with defects in the synthesis or expression of capsule. The most common mutant phenotype was acapsular (K-), with no K-antigen synthesized.