Fecal Microbiota Transplantation: Expanding Horizons for Clostridium difficile Infections and Beyond.

Fecal Microbiota Transplantation (FMT) methodology has been progressively refined over the past several years. The procedure has an extensive track record of success curing Clostridium difficile infection (CDI) with remarkably few adverse effects. It achieves similar levels of success whether the CDI occurs in the young or elderly, previously normal or profoundly ill patients, or those with CDI in Inflammatory Bowel Disease (IBD).

Three distinct messenger RNAs can encode the human immunosuppressant-binding protein FKBP12.

FKBP12 is an 11.8-kDa protein that binds the potent immunosuppressants FK506 and rapamycin. When bound to FK506, FKBP12 forms an inhibitory complex with calcineurin and interferes with signal transduction in activated T lymphocytes.

Cloning, genomic organization and transcription of the Entamoeba histolytica alpha-tubulin-encoding gene.

We have isolated and characterized an Entamoeba histolytica alpha-tubulin (alpha Tub)-encoding gene (Eh alpha tub). A 700-bp DNA fragment was amplified by PCR using primers derived from consensus alpha- and beta-Tub amino acid (aa) sequences from different organisms and E. histolytica DNA as the template.

Overexpression of p59-HBI (FKBP59), full length and domains, and characterization of PPlase activity.

It has been previously proposed that the rabbit p59-HBI (Heat shock protein Binding Immunophilin) or rFKBP59 (FK506 Binding Protein), found associated with the 90 kDa heat shock protein in nontransformed steroid receptor complexes, has three domains structurally related to hFKBP12 (Callebaut, I., Renoir, J.M.

Structure-based drug design: applications in immunopharmacology and immunosuppression.

Structure-based drug design (SBDD) combines the power of many scientific disciplines, such as X-ray crystallography, nuclear magnetic resonance, medicinal chemistry, molecular modeling, biology, enzymology and biochemistry, in a functional paradigm of drug development. The current strength of SBDD lies in parlaying enzyme inhibitors into drugs, but a variety of technological advances over the past few years now makes it possible to address complex biological targets, such as those regulating immunosuppression and immunoactivation. Manual Navia and Debra Peattie discuss the SBDD paradigm and consider several of its achievements and challenges in immunopharmacology, particularly as these apply to the design of novel, potent immunosuppressants.

Structure-based drug design: applications in immunopharmacology and immunosuppression.

Structure-based drug design (SBDD) combines the power of many scientific disciplines, such as X-ray crystallography, nuclear magnetic resonance, medicinal chemistry, molecular modeling, biology, enzymology and biochemistry, in a functional paradigm of drug development. The current strength of SBDD lies in parlaying enzyme inhibitors into drugs, but a variety of technological advances over the past few years now makes it possible to address complex biological targets, such as those regulating immunosuppression and immunoactivation. Manuel Navia and Debra Peattie discuss the SBDD paradigm and consider several of its achievements and challenges in immunopharmacology, particularly as these apply to the design of novel, potent immunosuppressants.

Expression and characterization of human FKBP52, an immunophilin that associates with the 90-kDa heat shock protein and is a component of steroid receptor complexes.

Using an FK506 affinity column to identify mammalian immunosuppressant-binding proteins, we identified an immunophilin with an apparent M(r) approximately 55,000, which we have named FKBP52. We used chemically determined peptide sequence and a computerized algorithm to search GenPept, the translated GenBank data base, and identified two cDNAs likely to encode the murine FKBP52 homolog. We amplified a murine cDNA fragment, used it to select a human FKBP52 (hFKBP52) cDNA clone, and then used the clone to deduce the hFKBP52 sequence (calculated M(r) 51,810) and to express hFKBP52 in Escherichia coli.

Identification and characterization of gamma-giardin and the gamma-giardin gene from Giardia lamblia.

The giardins are abundant cytoskeletal proteins that range in size from 29-38 kDa and are specific to the ventral disk of the intestinal protozoan parasite Giardia lamblia. The 29-kDa (beta and beta-1; refs. 8-10) and the 33-kDa (alpha-1 and alpha-2; refs.

Nucleotide sequence of a second alpha giardin gene and molecular analysis of the alpha giardin genes and transcripts in Giardia lamblia.

The giardins are a group of proteins with relative molecular masses (Mrs) between 29,000 and 38,000 that are specific to the ventral disk of the intestinal protozoan parasite Giardia lamblia. We previously have characterized alpha-giardin, renamed here alpha-1-giardin, as a novel 33-kDa protein located on the edges of the disk microribbons. Southern blot analysis of G.

cDNA encoding murine FK506-binding protein (FKBP): nucleotide and deduced amino acid sequence.

A FKBP cDNA encoding murine FK506 binding protein (FKBP) has been cloned, and its complete nucleotide sequence has been determined. The open reading frame within the 1556-bp cDNA segment encodes an 108 amino acid (aa) protein that differs from the human FKBP by three aa and from the bovine FKBP by five aa. Molecular modeling of the protein places the aa substitutions at positions not directly involved in drug binding or interaction with the potential drug target protein, calcineurin A.

Solution structure of the major binding protein for the immunosuppressant FK506.

The major FK506 binding protein (FKBP, relative molecular mass approximately 11,800; Mr 11.8K) and cyclophilin (Mr approximately 17K) belong to a class of proteins termed immunophilins. Although unrelated at the amino-acid sequence level, they both possess peptidyl-prolyl cis-trans isomerase activities which are inhibited by immunosuppressants that block signal transduction pathways leading to T-lymphocyte activation.

Chromatin organization in Entamoeba histolytica.

The chromatin structure of Entamoeba histolytica was investigated. It was found that this protozoan organizes its chromatin in nucleosome-like particles 10 nm in diameter, but digestion of the chromatin with micrococcal nuclease did not render a regularly spaced DNA ladder in agarose gels. Southern blot analysis of the products of Entamoeba chromatin digestion using total amebic DNA and a non-transcribed repetitive sequence produced a banding pattern characteristic of eukaryotic chromatin with a repetitive size of approximately 130 bp.

In situ analyses reveal that the two nuclei of Giardia lamblia are equivalent.

The protozoan parasite Giardia lamblia has the unusual morphology of bearing two equal-sized nuclei. This organism probably represents the earliest diverging lineage of eukaryotes, suggesting that its biological tactics may be transitional. To begin to understand the role played by the two equal-sized nuclei in this organism, and perhaps the role this organism has played along the path to higher eukaryotes, we have analyzed the structure and function of these two nuclei.

The giardins of Giardia lamblia: genes and proteins with promise.

The unique evolutionary position of the genus Giardia recently came to light when Mitch Sogin and colleagues showed it to be the earliest diverging lineage in the eukaryotic line of descent by ribosomal RNA analysis. Similar in significance, the acquisition of a cytoskeleton was a pivotal occurrence in evolution. With an endoskeleton came an internal support structure for cells as well as the means to regulate dynamic phenomena such as muscle contraction, mitotic movement of chromosomes, ciliar and flagellar beating, and cell migration.

Ultrastructural localization of giardins to the edges of disk microribbons of Giarida lamblia and the nucleotide and deduced protein sequence of alpha giardin.

The giardins are a group of 29-38-kD proteins in the ventral disk of the protozoan parasite Giardia lamblia. The disk attaches the parasite to the host's intestinal epithelium and is composed of parallel, coiled microtubules that are adjacent to the ventral plasma membrane and from which processes called microribbons extend into the cytoplasm; the microribbons are connected by crossbridges. G.

Structure and expression of a family of Ultrabithorax mRNAs generated by alternative splicing and polyadenylation in Drosophila.

The 77-kb primary transcript of the homeotic Ultrabithorax (Ubx) gene is alternatively spliced to yield at least five different coding regions. Each is restricted to either a 3.2- or a 4.

Phylogenetic meaning of the kingdom concept: an unusual ribosomal RNA from Giardia lamblia.

An analysis of the small subunit ribosomal RNA (16S-like rRNA) from the protozoan Giardia lamblia provided a new perspective on the evolution of nucleated cells. Evolutionary distances estimated from sequence comparisons between the 16S-like rRNAs of Giardia lamblia and other eukaryotes exceed similar estimates of evolutionary diversity between archaebacteria and eubacteria and challenge the phylogenetic significance of multiple eukaryotic kingdoms. The Giardia lamblia 16S-like rRNA has retained many of the features that may have been present in the common ancestor of eukaryotes and prokaryotes.

Novel transcripts from the Ultrabithorax domain of the bithorax complex.

We present a detailed analysis of the transcriptional products of the bithoraxoid (bxd) region of the Ultrabithorax domain in the bithorax complex of Drosophila melanogaster. This region is transcribed twice during development: between 3 and 6 hr of embryogenesis, a set of early transcripts, 1.1 to 1.

Alternative conformers of 5S ribosomal RNA and their biological relevance.

Different conformational states of Escherichia coli 5S ribosomal RNA that may participate in protein biosynthesis have been either detected experimentally or predicted on the basis of phylogenetic sequence comparisons. The A conformer exists in a high-salt form (AH) that binds ribosomal proteins and assembles into the 50S subunit and in a low-salt form (AL), of uncertain biological relevance, that binds at least one ribosomal protein and differs in tertiary structure from the AH form. Experimentally, the AH form has been investigated comprehensively and the AL form partially.

A "bulged" double helix in a RNA-protein contact site.

The binding of ribosomal protein L18 affects specific nucleotides in Escherichia coli 5S RNA as detected by dimethyl sulfate alkylation and RNase A digestion of the 5S-L18 complex. Most of the affected nucleotides are clustered and localize a site of RNA-protein interaction in and around the defined central helix [Fox, G. E.

Chemical probing of the tRNA--ribosome complex.

We probed the (Escherichia coli) tRNAPhe--ribosome interaction with the chemical reagents dimethyl sulfate and diethyl pyrocarbonate. This monitored the higher-order structure of the tRNA in this biological complex and identified critical sites in the tRNA molecule involved in binding to the ribosome. The methylation of the N-7 position of guanosine and the N-3 position of cytidine as well as diethyl pyrocarbonate attack on adenosines are sensitive to secondary and tertiary interactions.