Hybrid Gene Origination Creates Human-Virus Chimeric Proteins during Infection.

RNA viruses are a major human health threat. The life cycles of many highly pathogenic RNA viruses like influenza A virus (IAV) and Lassa virus depends on host mRNA, because viral polymerases cleave 5'-m7G-capped host transcripts to prime viral mRNA synthesis ("cap-snatching"). We hypothesized that start codons within cap-snatched host transcripts could generate chimeric human-viral mRNAs with coding potential.

Norovirus translation requires an interaction between the C Terminus of the genome-linked viral protein VPg and eukaryotic translation initiation factor 4G.

Viruses have evolved a variety of mechanisms to usurp the host cell translation machinery to enable translation of the viral genome in the presence of high levels of cellular mRNAs. Noroviruses, a major cause of gastroenteritis in man, have evolved a mechanism that relies on the interaction of translation initiation factors with the virus-encoded VPg protein covalently linked to the 5' end of the viral RNA. To further characterize this novel mechanism of translation initiation, we have used proteomics to identify the components of the norovirus translation initiation factor complex.

Development of an optimized RNA-based murine norovirus reverse genetics system.

Murine norovirus (MNV), identified in 2003, is the only norovirus which replicates efficiently in tissue culture and as a result has been used extensively as a model for human noroviruses, a major cause of acute gastroenteritis. The current report describes the generation of a new approach to reverse genetics recovery of genetically defined MNV that relies on the transfection of in vitro transcribed capped RNA directly into cells. The use of the recently developed ScriptCap post-transcriptional enzymatic capping system, followed by optimized Neon mediated electroporation of the highly permissive RAW 264.

Functional analysis of RNA structures present at the 3' extremity of the murine norovirus genome: the variable polypyrimidine tract plays a role in viral virulence.

Interactions of host cell factors with RNA sequences and structures in the genomes of positive-strand RNA viruses play various roles in the life cycles of these viruses. Our understanding of the functional RNA elements present in norovirus genomes to date has been limited largely to in vitro analysis. However, we recently used reverse genetics to identify evolutionarily conserved RNA structures and sequences required for norovirus replication.

Development of a multi-locus sequence typing scheme for Laribacter hongkongensis, a novel bacterium associated with freshwater fish-borne gastroenteritis and traveler's diarrhea.

Background: Laribacter hongkongensis is a newly discovered, facultative anaerobic, Gram-negative, motile, sea gull-shaped rod associated with freshwater fish borne gastroenteritis and traveler's diarrhea. A highly reproducible and discriminative typing system is essential for better understanding of the epidemiology of L. hongkongensis.

MP1 homologue-based multilocus sequence system for typing the pathogenic fungus Penicillium marneffei: a novel approach using lineage-specific genes.

A highly reproducible and discriminative typing system is essential for better understanding of the epidemiology of Penicillium marneffei, the most important thermal dimorphic fungus causing respiratory, skin, and systemic mycosis in Southeast Asia. The sequences of 11 housekeeping genes were identical among 10 strains of P. marneffei, but those of MP1 and its 13 homologues, a novel superfamily of mannoproteins in the subdivision Pezizomycotina of Ascomycetes, mostly species of Penicillium and Aspergillus, showed significant variations.

Catabacter hongkongensis gen. nov., sp. nov., isolated from blood cultures of patients from Hong Kong and Canada.

Four bacterial isolates were recovered from the blood cultures of four patients, two of whom were from Hong Kong and two of whom were from Canada. The two Hong Kong strains were isolated from a 48-year-old man with intestinal obstruction and secondary sepsis (strain HKU16T) and from a 39-year-old man with acute appendicitis (strain HKU17), while the two Canadian strains were isolated from a 74-year-old man with biliary sepsis (strain CA1) and from a 66-year-old woman with metastatic carcinoma and sepsis (strain CA2). While the first three patients survived, the last patient died 2 weeks after the episode of bacteremia.

In silico analysis of 16S ribosomal RNA gene sequencing-based methods for identification of medically important anaerobic bacteria.

This study is the first study that provides useful guidelines to clinical microbiologists and technicians on the usefulness of full 16S rRNA sequencing, 5'-end 527-bp 16S rRNA sequencing and the existing MicroSeq full and 500 16S rDNA bacterial identification system (MicroSeq, Perkin-Elmer Applied Biosystems Division, Foster City, California, USA) databases for the identification of all existing medically important anaerobic bacteria. Full and 527-bp 16S rRNA sequencing are able to identify 52-63% of 130 Gram-positive anaerobic rods, 72-73% of 86 Gram-negative anaerobic rods and 78% of 23 anaerobic cocci. The existing MicroSeq databases are able to identify only 19-25% of 130 Gram-positive anaerobic rods, 38% of 86 Gram-negative anaerobic rods and 39% of 23 anaerobic cocci.