ABSTRACT
Enteroaggregative Escherichia coli (EAggEC) are an important cause of diarrhea. Four types of AAF have been identified; however, their prevalence and association with virulence properties remain unclear. E. coli strains carrying the aggR gene as EAggEC that were isolated in Japan and Thailand (n = 90) were examined for AAF subunit genes, two toxin genes (pet/astA), and clump formation. The most prevalent AAF gene was hdaA (28%), followed by aafA (20%), aggA (12%), and agg3A (4%), as well as a putative new AAF sequence (25.6%). Retention status of the toxin genes and intensities of clump formation appeared to vary according to the AAF type.
Subject(s)
Bacterial Adhesion , Escherichia coli Infections/microbiology , Escherichia coli Proteins/metabolism , Escherichia coli/isolation & purification , Fimbriae, Bacterial/metabolism , Trans-Activators/metabolism , Escherichia coli/classification , Escherichia coli/genetics , Escherichia coli/physiology , Escherichia coli Proteins/genetics , Fimbriae, Bacterial/genetics , Humans , Japan , Thailand , Trans-Activators/genetics , Virulence Factors/genetics , Virulence Factors/metabolismSubject(s)
Influenza A Virus, H3N2 Subtype/genetics , Influenza A Virus, H3N2 Subtype/isolation & purification , Influenza, Human/virology , Aviation , Genes , Hemagglutination Inhibition Tests , Humans , Influenza, Human/epidemiology , Molecular Epidemiology , Phylogeny , Sequence Analysis, DNA , TravelABSTRACT
Using the newly designed mismatch amplification mutation assay (MAMA) PCR, we demonstrated the high frequency of amantadine-resistant influenza A (H3N2) viruses isolated during the 2005-2006 season by detecting the mutation at amino acid position 31 of the M2 protein (S31N). Further, phylogenetic analyses of the HA1 sequences of the S31N viruses revealed that they comprised a clonal lineage that would result in the common characteristic amino acid changes at positions 193 (Ser to Phe) and 225 (Asp to Asn) of the HA protein. We also demonstrated that the S31N/S193F/D225N viruses had already emerged in Aichi Prefecture by the end of the previous 2004-2005 season.
Subject(s)
Amantadine/pharmacology , Antiviral Agents/pharmacology , Influenza A Virus, H3N2 Subtype/genetics , Influenza, Human/virology , Reverse Transcriptase Polymerase Chain Reaction/methods , Base Pair Mismatch , Base Sequence , Drug Resistance, Viral , Humans , Influenza A Virus, H3N2 Subtype/drug effects , Influenza A Virus, H3N2 Subtype/isolation & purification , Molecular Sequence Data , Mutation , Phylogeny , Viral Matrix Proteins/geneticsABSTRACT
An influenza C virus was isolated from a Japanese traveler who had visited Malaysia in April 1999. Phylogenetic analysis indicated that the genome composition of this virus was distinct from that of any other strain isolated in Japan. The possibility that a genetically unique influenza C virus was introduced into Japan by a traveler is shown.
