Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals (i) extensive alternative pathways for energy generation, (ii) Ϸ500 ORFs for transport-related proteins, (iii) complex and extensive systems for stress adaptation and motility, and (iv) widespread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for the detoxification of xenobiotics that may have biotechnological applications.T he genomes of soil-and water-borne free-living bacteria have received relatively little attention thus far in comparison to pathogenic and extremophilic organisms, yet they provide fundamental insights into environmental adaptation strategies and represent a rich source of genes with biotechnological potential and medical utility. A particularly interesting organism of this kind is Chromobacterium violaceum, a Gram-negative ␤-proteobacterium first described at the end of the 19th century (1), which dominates a variety of ecosystems in tropical and subtropical regions. This bacterium has been found to be highly abundant in the water and borders of the Negro river, a major component of the Brazilian Amazon (2) and as a result has been studied in Brazil over the last three decades. These, in general, have focused on the most notable product of the bacterium, the violacein pigment, which has already been introduced as a therapeutic compound for dermatological purposes (3). Violacein also exhibits antimicrobial activity against the important tropical pathogens Mycobacterium tuberculosis (4), Trypanosoma cruzi (5), and Leishmania sp. (6) and is reported to have other bactericidal (2, 7-10), antiviral (11), and anticancer (12, 13) activities.Some other aspects of the biotechnological potential of C. violaceum have also begun to be explored, including the synthesis of poly(3-hydroxyvaleric acid) homopolyester and other shortchain polyhydroxyalkanoates, which might represent alternatives to plastics derived from petrochemicals (14, 15), the hydrolysis of plastic films (16), and the solubilization of gold through a mercury-free process, thereby avoiding environmental contamination (17, 18). These studies, however, have been based on knowledge of only a tiny fraction of the genetic constitution of the organism. In addition, the more basic issues of the mechanisms and strategies underlying the adaptability of C. violaceum, including its observed but infrequent infection of h...

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The prevalence, seasonality, and genotype distribution of rotavirus infection varied in different regions in Brazil. With immunization programs, continuous monitoring of rotavirus types is important to detect novel and emerging strains.

Key words: rotavirus -gastroenteritis -epidemiology -seasonality - Goiás -Brazil Diarrhoea is an important cause of morbidity in humans throughout the world, affecting mainly infants and children . Group A rotavirus is the most common cause of acute gastroenteritis in young children, causing a large number of hospitalizations (Pérez-Schael et al. 1999). Rotavirus is also associated with child mortality in several countries (Bern et al. 1992, Argüelles et al. 2000, Kapikian et al. 2001. This virus was detected for the first time in Brazil in 1976 (Linhares et al. 1977). After that description, several investigations were made and results demonstrated the relevance of rotavirus in the etiology of diarrhoea throughout the country (Rácz et al. 1988, Pereira et al. 1993, Leite et al. 1996.This study presents results from a rotavirus surveillance in Goiânia, Goiás. Our analysis was focused on the role of the virus in the diarrhoeal illness, as well as on ageprevalence and seasonality of rotavirus infection in the region. out diarrhoea from three different settings: children admitted to three hospitals (Hospital Materno Infantil, Hospital das Clínicas, and Hospital Lúcio Rebelo); children seen in outpatient clinics of Hospital Lúcio Rebelo, and children attending several day-care centers. Three or more liquid or semi-liquid daily evacuations were considered as diarrhoea, along with available medical information. Associated symptoms included vomit, fever and abdominal pain. The children enrolled in the study belonged to low socio-economic strata, according to the information provided by their parents/legal guardians. The faecal specimens were collected from the children only after a written consent was provided by parents/legal guardians. Also, ethical approval was obtained from the Ethics Committee on Research of the Federal University of Goiás. MATERIALS AND METHODS SubjectCharacteristics of the samples and of the childrenFrom 2,605 faecal specimens, 1,494 (57.4%) were collected from hospitalized patients. Of the remainder faecal specimens, 528 (20.3%) were obtained from children seen in outpatient clinics, and 583 (22.4%) in day-care centers. The investigation in hospitals began in 1986 and continued until 2000, except for the 1995-1997 period, when no samples were collected. In outpatient clinics the collection of the faecal specimens took place from 1986 to 1995, while in day-care centers samples were collected from 1989 to 1994. From the total number of fecal samples, 1,324 (50.8%) samples were collected from children with diarrhoea, and 1,246 (94.1%) of these children were hospitalized. From the remaining samples, 1,281 (49.2%) came from children who presented either with other symptoms than diarrhoea or with no symptoms. From those 480 (37.5%) were from outpatient clinics. All children with no symptoms were from day-care centers. Regarding the gender

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