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SummarySerratia marcescens SS-1 produces at least four N -acylhomoserine lactones (AHLs) which were identified using high-resolution mass spectrometry and chemical synthesis, as N-(3-oxohexanoyl) homoserine lactone (3-oxo-C6-HSL), N -hexanoyl-(C6-HSL), N -heptanoyl (C7-HSL) and N -octanoyl-(C8-HSL) homoserine lactone. These AHLs are synthesized via the LuxI homologue SpnI, and regulate via the LuxR homologue SpnR, the production of the red pigment, prodigiosin, the nuclease, NucA, and a biosurfactant which facilitates surface translocation. spnR overexpression and spnR gene deletion show that SpnR, in contrast to most LuxR homologues, acts as a negative regulator. spnI overexpression, the provision of exogenous AHLs and spnI gene deletion suggest that SpnR is de-repressed by 3-oxo-C6-HSL. In addition, long chain AHLs antagonize the biosurfactantmediated surface translocation of S. marcescens SS-1. Upstream of spnI there is a gene which we have termed spnT . spnI and spnT form an operon and although database searches failed to reveal any spnT homologues, overexpression of this novel gene negatively affected both sliding motility and prodigiosin production.

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To our knowledge, Flavobacterium indologenes has never been reported as a cause of bacteremia in humans. F. indologenes bacteremia was diagnosed in 12 patients at a tertiary referral center in southern Taiwan between 1 January 1992 and 31 December 1994. Six of these patients had ventilator-associated pneumonia, two had primary bacteremia, and one patient each had pyonephrosis, peritonitis, biliary tract infection, and surgical wound infection. Five patients (42%) had malignancies, and three (25%) had multiple burns. Polymicrobial bacteremia was diagnosed in eight patients (67%). Two (17%) of the patients in this study died; both had polymicrobial bacteremia. Antimicrobial susceptibility testing of the blood isolates from the 12 patients showed that > 90% of the isolates were susceptible to piperacillin, cefoperazone, ceftazidime, and minocycline. The chromatograms of esterified fatty acids for the isolates were identical. F. indologenes should be considered an etiologic agent of bloodstream infection, especially in hospitalized patients with severe underlying diseases.

We developed an interactive mobile-phone based application, SmartDiet, that analyzes daily nutrition intake and patterns of daily exercise. It provides a personalized diet profile and promotes knowledge about nutrition using a diet game. We evaluated the effectiveness of the SmartDiet application in terms of acquiring dietary information, weight control and user satisfaction. A case-control study was conducted over a six-week period, with 19 people in the intervention group and 17 people in the control group. During the study, a total of 235 successful data transmissions were performed from the mobile phones and there was a mean of 12.4 transmissions per participant. The three body composition measures (fat mass, weight and body mass index) decreased significantly after the intervention in the intervention group, but there were no significant changes in the control group. In a questionnaire survey at the end of the study, the majority of the participants responded that the system was useful for obtaining information and managing the diet process. The SmartDiet mobile weight management application appears to contribute to weight loss in obese adults.

From January 1995 to September 1996, 14 isolates of Sphingomonas paucimobilis, including 11 from clinical specimens from six patients with nosocomial infection and three from environmental sources, were collected. Two of the six patients had intravascular catheter-related bacteremia and one each had bacteremic biliary tract infection, urinary tract infection, ventilator-associated pneumonia, and wound infection. The S. paucimobilis isolates were identified according to biochemical profiles established with use of the API 20NE system and Vitek GNI card and the characteristic cellular fatty acid chromatogram. Ten biotypes, 11 antibiograms (by the Etest), and 12 random amplified polymorphic DNA (RAPD) patterns (by arbitrarily primed polymerase chain reaction) were identified. The identical biotype, antibiogram, and RAPD pattern of the two isolates (one each from blood and bile) from a patient with biliary tract infection indicated the invasiveness of the organism. Two patients with intravascular catheter-related bacteremia had isolates of this organism repeatedly recovered, and these isolates had heterogeneous RAPD patterns. The present study highlights the wide distribution in hospital environments of various clones of S. paucimobilis, which may cause recurrent infections by a single strain or several episodes of infection due to two or more clones of this organism in hospitalized patients.

The in vitro susceptibilities of 266 isolates of Streptococcus agalactiae determined by the agar dilution method showed that 6% of isolates were nonsusceptible to penicillin and 46% was resistant to erythromycin. Of the erythromycin-resistant isolates, 86.3% had the macrolide-lincosamide-streptogramin (MLS) resistance phenotype (constitutive MLS, 85.5%; inducible MLS, 0.8%) and 13.7% had the M phenotype.

The full-length sequences of the groESL genes (also known as cpn10/60) of Streptococcus anginosus, Streptococcus constellatus, Streptococcus gordonii, and Streptococcus sanguis and the near full-length sequence of the groESL genes of Streptococcus intermedius, Streptococcus bovis, Streptococcus mitis, Streptococcus mutans, Streptococcus oralis, and Streptococcus salivarius were determined. The lengths of the groES genes from the 10 species listed above ranged from 282 to 288 bp, and the full-length sequences of groEL determined for 4 species (S. anginosus, S. constellatus, S. gordonii, and S. sanguis) revealed that each was 1,623 bp. The intergenic region (spacer) between the groES and groEL genes varies in size (15 to 111 bp) and sequence between species. The variation of the groES sequences among the species tested was greater (62.1 to 95.1% nucleotide sequence identities) than that of the groEL sequences (77.2 to 95.2% nucleotide sequence identities). Phylogenetic analysis of the groES and groEL genes yielded evolutionary trees similar to the tree constructed by use of the 16S rRNA gene. The intraspecies variation of the spacer was minimal for clinical isolates of some species. The groESL sequence data provide an additional parameter for identification of viridans group streptococcal species.Viridans group streptococci (VGS) are the most common etiologic agents in subacute infective endocarditis and are known to be capable of causing many serious pyogenic infections (1,4,14). Since the clinical significance of VGS may differ between species, it is important to identify the individual species associated with diseases and to recognize their pathogenic traits (14). Moreover, increases in rates of antimicrobial resistance have been noted among VGS (25). The difference in susceptibilities between species of VGS indicates the importance of accurate identification. At present, the species of VGS can be divided into five major groups according to their 16S rRNA sequences (15). These are (i) the anginosus group (also called the milleri group), which includes At present, species identification of VGS is based on physiological and biochemical characteristics determined by conventional methods, which are time-consuming (6). Many clinical laboratories rely on manual or automated phenotypic test systems. However, there have been variations among physiological reactions within the same species, and misidentification has occurred, particularly for some species. S. mutans strains and strains of the anginosus and mitis groups are the most problematic (12, 29). Differentiation of species within the same group is often difficult (6, 27). Another approach to species identification may be the use of molecular methods. Several DNA-based techniques have been developed for the identification of VGS to the species level (3,7,8,13,16,21,23,24,28). The target genes have included 16S rRNA genes, the tRNA gene intergenic spacer, 16S-23S rRNA spacers, the gene for D-alanine-D-alanine ligase, and the gene for manganese-dependent superoxide ...