A high prevalence of Clostridium botulinum type E in Finnish freshwater and Baltic Sea sediment samples

The distribution of Clostridium botulinum serotypes A, B, E and F in aquatic environments of the Baltic Sea and Finnish mainland was examined. A total of 110 samples were tested with a neurotoxin-specific PCR assay. Clostridium botulinum type E was found in 81% of sea and 61% of freshwater samples. No other toxinotypes were found. Spore counts were quantified by the most probable number method, Cl. botulinum type E kg⁻¹ averaging 940 in sea and 370 in freshwater samples. The overall prevalence and spore counts of Cl. botulinum type E in aquatic sediments correlated significantly with offshore bottom oxygen content, depth, and bioturbation activity, whereas there was no correlation with bottom water temperature. These findings indicate the possibility of Cl. botulinum type E multiplication or at least, suitable conditions for spore survival, in anoxic sediments.     

A high prevalence of Clostridium botulinum type E in Finnish freshwater and Baltic Sea sediment samples

The distribution of Clostridium botulinum serotypes A, B, E and F in aquatic environments of the Baltic Sea and Finnish mainland was examined. A total of 110 samples were tested with a neurotoxin-specific PCR assay. Clostridium botulinum type E was found in 81% of sea and 61% of freshwater samples. No other toxinotypes were found. Spore counts were quantified by the most probable number method, Cl. botulinum type E kg(-1) averaging 940 in sea and 370 in freshwater samples. The overall prevalence and spore counts of Cl. botulinum type E in aquatic sediments correlated significantly with offshore bottom oxygen content, depth, and bioturbation activity, whereas there was no correlation with bottom water temperature. These findings indicate the possibility of Cl. botulinum type E multiplication or at least, suitable conditions for spore survival, in anoxic sediments.     

Phylogeography of North Atlantic intertidal tardigrades: refugia,cryptic speciation and the history of the Mid‐Atlantic Islands

Aim To analyse the phylogeographical history of intertidal tardigrades in the North Atlantic in order to improve our understanding of geographical differentiation in microscopic organisms, and to understand the potential importance of the Mid‐Atlantic Islands as stepping stones between the American and European coasts of the Atlantic Ocean. Location Twenty‐four localities from the Mid‐Atlantic Islands (Greenland, Iceland and the Faroe Islands) and both sides of the North Atlantic Ocean. Methods A mitochondrial marker (cytochrome c oxidase subunit I) was sequenced from individual tardigrades belonging to the genus Echiniscoides. The existence of cryptic species was detected using generalized mixed Yule coalescence analysis; lineage ages were estimated with relaxed clock methods; and the degree of geographical differentiation was analysed with samova analyses, haplotype networks and Mantel tests. Results Echiniscoides hoepneri, previously known only from Greenland, was recovered throughout the Mid‐Atlantic Islands. The Faroe Islands population was isolated from Greenland and Iceland, but overall genetic variation was low. The morphospecies Echiniscoides sigismundi had high genetic variation and consisted of at least two cryptic species. A northern and a southern species were both recovered on both sides of the Atlantic, but only the northern species was found on the Mid‐Atlantic Islands. The northern species showed signs of long‐term isolation between the Western and Eastern Atlantic, despite the potential of the Mid‐Atlantic islands to act as stepping‐stones. There was no sign of long‐term isolation in the southern species. The Mid‐Atlantic individuals of the northern species were of Eastern Atlantic origin, but Greenland and Iceland showed signs of long‐term isolation. The genetic pattern found in the southern species is not clearly geographical, and can probably be best explained by secondary contact between former isolated populations. Main conclusions North Atlantic intertidal tardigrades from the genus Echiniscoides showed strong geographical differentiation, and the Mid‐Atlantic Islands seemed unimportant as stepping stones across the Atlantic. The geographical variation of the northern species of E. sigismundi suggests post‐glacial recolonization from several refugia.     

Norse Greenland settlement: reflections on climate change, trade, and the contrasting fates of human settlements in the North Atlantic Islands

Changing economies and patterns of trade, rather than climatic deterioration, could have critically marginalized the Norse Greenland settlements and effectively sealed their fate. Counter-intuitively, the end of Norse Greenland might not be symptomatic of a failure to adapt to environmental change, but a consequence of successful wider economic developments of Norse communities across North Atlantic. Data from Greenland, the Faroe Islands, and medieval Iceland is used to explore the interplay of Norse society with climate, environment, settlement, and other circumstances. Long term increases in vulnerability caused by economic change and cumulative climate changes sparked a cascading collapse of integrated interdependent settlement systems, bringing the end of Norse Greenland.     

New insights into the biodiversity and generic relationships of foliose Bangiales (Rhodophyta) in Iceland and the Faroe Islands

Foliose species of the Bangiales (Porphyra sensu lato) have a long history of study in the N Atlantic, but there are still regions, especially in the northern parts of the N Atlantic that need more attention. A molecular study using rbcL and cox1 sequences was undertaken to assess the diversity of foliose Bangiales species in Iceland and the Faroe Islands. Herbarium collections from the intertidal and subtidal of Iceland (summer and winter) and the Faroe Islands (all seasons) revealed a total of 13 species (11 common to both areas), which were referred to four of the genera recognized in a recent two-gene global phylogeny. Boreophyllum birdiae, Porphyra dioica, P. linearis, P. purpurea, P. umbilicalis, Pyropia ‘leucosticta’ A, Pyropia njordii Mols-Mortensen, J. Brodie & Neefus, sp. nov., Wildemania amplissima and W. miniata were common to both areas, while Pyropia thulaea and Wildemania abyssicola (Kjellman) A. Mols-Mortensen & J. Brodie, comb. nov. (=Porphyra abyssicola Kjellman) were reported from Iceland but not from the Faroe Islands; Porphyra sp. FO and Pyropia elongata were reported from the Faroe Islands but not from Iceland. Boreophyllum birdiae is reported for the first time for Iceland and Porphyra sp. FO is reported for the first time for the Faroe Islands. Pyropia njordii is described from the Faroe Islands and is also recorded for Iceland, Greenland, New England, USA and Nova Scotia, Canada. A total of 25 foliose Bangiales species are now reported from the N Atlantic and these results demonstrate the importance of investigating as many areas as possible to reach a more complete understanding of species diversity and distribution.     

Biodiversity of Clostridium botulinum type E associated with a large outbreak of botulism in wildlife from Lake Erie and Lake Ontario

The genetic relatedness of Clostridium botulinum type E isolates associated with an outbreak of wildlife botulism was studied using random amplification of polymorphic DNA (RAPD). Specimens were collected from November 2000 to December 2008 during a large outbreak of botulism affecting birds and fish living in and around Lake Erie and Lake Ontario. In our present study, a total of 355 wildlife samples were tested for the presence of botulinum toxin and/or organisms. Type E botulinum toxin was detected in 110 samples from birds, 12 samples from fish, and 2 samples from mammals. Sediment samples from Lake Erie were also examined for the presence of C. botulinum. Fifteen of 17 sediment samples were positive for the presence of C. botulinum type E. Eighty-one C. botulinum isolates were obtained from plants, animals, and sediments; of these isolates, 44 C. botulinum isolates produced type E toxin, as determined by mouse bioassay, while the remaining 37 isolates were not toxic for mice. All toxin-producing isolates were typed by RAPD; that analysis showed 12 different RAPD types and multiple subtypes. Our study thus demonstrates that multiple genetically distinct strains of C. botulinum were involved in the present outbreak of wildlife botulism. We found that C. botulinum type E is present in the sediments of Lake Erie and that a large range of bird and fish species is affected.     

Comparing Norse animal husbandry practices: paleoethnobotanical analyses from Iceland and Greenland

The popular view of the Norse settlement across the North Atlantic describes colonies with similar subsistence practices being established from the Faroe Islands in the west to L'Anse aux Meadows in the east. The importance of plant resources to the Norse animal husbandry strategies implemented by settlers upon arrival are not well established, nor are the changes these strategies underwent, eventually resulting in different cultural solutions to varying environmental and social factors. This paper compares archaeobotanical samples from two Icelandic archaeological sites, Svalbare and Gj?gur, and one Greenlandic site, G?rden Under Sandet (GUS). Results of this comparison suggest that heathland shrubs were an important fodder resource for caprines in both Iceland and Greenland while apophytes ("weedy taxa") were part of the cattle fodder in Greenland. Further, the results indicate that mucking out of cattle barns to provide fertilizer was likely practiced at the GUS site in the Western Norse settlement of Greenland.     

Prevalence of Clostridium botulinum type E and coexistence of C. botulinum nonproteolytic type B in the river soil of Japan.

Soil samples from 98 sites in the whole systems of four rivers in Japan were examined for the presence of Clostridium botulinum. Type E organism was prevalently shown throughout the whole river systems including upper part; detection rates of type E toxin in soil culture ranged from 33 to 82%. This type was also detected in soil of adjacent mountainous district. Type B and C toxins were detected at 7% and 9% of the sites examined, respectively. C. botulinum type E and nonproteolytic type B strains were isolated from enrichment cultures of soil samples. These results suggest that the terrestrial origin of type E organism would be considered as one of the reasons for the high incidence of this organism in the sea areas, and prove that C. botulinum nonproteolytic type B exists in the soil of Japan.     

Ecology of Vibrio mimicus in aquatic environments

An environmental study was done to examine the prevalence of Vibrio mimicus in some aquatic environments of Dhaka, Bangladesh, and of Okayama, Japan. Water samples from Dhaka environments and water and plankton samples from Okayama environments were quantitatively as well as qualitatively analyzed throughout the seasons for V. mimicus. The organism was isolated from Bangladesh environments throughout the year, whereas it was not isolated in Okayama when the water temperature fell below 10 degrees C. Samples with as many as 9.0 x 10(2) CFU of V. mimicus per 100 ml of water in Dhaka and 1.5 x 10(4) CFU of V. mimicus per 100 ml of water in Okayama were detected during the study period. V. mimicus was not found in any environment with an average salinity of 10% or more. Brackish environments with an average salinity of 4% were observed to be the optimal natural condition for the pathogen. Using the API 20E system with the conventional test methods, we observed variations in biochemical properties within the V. mimicus species. This study reveals the inefficacy of the API 20E system to identify a significant percentage of V. mimicus. Therefore, in addition to the API 20E system, a salt tolerance test and a string test are recommended for identification of this species. Susceptibility testing of strains isolated from Okayama environments showed higher resistance to ampicillin and susceptibility to trimethoprim-sulfamethoxazole when compared with environmental isolates of V. mimicus from Bangladesh.     

Ecology of Vibrio mimicus in aquatic environments.

An environmental study was done to examine the prevalence of Vibrio mimicus in some aquatic environments of Dhaka, Bangladesh, and of Okayama, Japan. Water samples from Dhaka environments and water and plankton samples from Okayama environments were quantitatively as well as qualitatively analyzed throughout the seasons for V. mimicus. The organism was isolated from Bangladesh environments throughout the year, whereas it was not isolated in Okayama when the water temperature fell below 10 degrees C. Samples with as many as 9.0 x 10(2) CFU of V. mimicus per 100 ml of water in Dhaka and 1.5 x 10(4) CFU of V. mimicus per 100 ml of water in Okayama were detected during the study period. V. mimicus was not found in any environment with an average salinity of 10% or more. Brackish environments with an average salinity of 4% were observed to be the optimal natural condition for the pathogen. Using the API 20E system with the conventional test methods, we observed variations in biochemical properties within the V. mimicus species. This study reveals the inefficacy of the API 20E system to identify a significant percentage of V. mimicus. Therefore, in addition to the API 20E system, a salt tolerance test and a string test are recommended for identification of this species. Susceptibility testing of strains isolated from Okayama environments showed higher resistance to ampicillin and susceptibility to trimethoprim-sulfamethoxazole when compared with environmental isolates of V. mimicus from Bangladesh.     

Development of enrichment semi-nested PCR for Clostridium botulinum types A, B, E, and F and its application to Korean environmental samples

An enrichment semi-nested PCR procedure was developed for detection of Clostridium botulinum types A, B, E, and F. It was applied to sediment samples to examine the prevalence of C. botulinum in the Korean environment. The first pair of primers for the semi-nested PCR was designed using a region shared by the types A, B, E, and F neurotoxin gene sequences, and the second round employed four nested primers complementary to the BoNT/A, /B, /E, and /F encoding genes for simultaneous detection of the four serotypes. Positive results were obtained from the PCR analysis of five of 44 sediments (11%) collected from Yeong-am Lake in Korea; all were identified as deriving from type B neurotoxin (bontb) genes. Two of the C. botulinum type B organisms were isolated, and their bontb genes sequenced. The deduced amino acid sequences of BoNT/B showed 99.5 and 99.8% identity with the amino acid sequence of accession no. AB084152. Our data suggest that semi-nested PCR is a useful tool for detecting C. botulinum in sediments, and renders it practicable to conduct environmental surveys.     

Detection by PCR-enzyme-linked immunosorbent assay of Clostridium botulinum in fish and environmental samples from a coastal area in northern France

The prevalence of Clostridium botulinum types A, B, E, and F was determined in 214 fresh fish and environmental samples collected in Northern France. A newly developed PCR-enzyme-linked immunosorbent assay (ELISA) used in this survey detected more than 80% of samples inoculated with fewer than 10 C. botulinum spores per 25 g and 100% of samples inoculated with more than 30 C. botulinum spores per 25 g. The percent agreement between PCR-ELISA and mouse bioassay was 88.9%, and PCR-ELISA detected more positive samples than the mouse bioassay did. The prevalence of C. botulinum in seawater fish and sediment was 16.6 and 4%, respectively, corresponding to 3.5 to 7 and 1 to 2 C. botulinum most-probable-number counts, respectively, and is in the low range of C. botulinum contamination reported elsewhere. The toxin type identification of the 31 naturally contaminated samples was 71% type B, 22.5% type A, and 9.6% type E. Type F was not detected. The high prevalence of C. botulinum type B in fish samples is relatively unusual compared with the high prevalence of C. botulinum type E reported in many worldwide and northern European surveys. However, fish processing and fish preparation in France have not been identified as a significant hazard for human type B botulism.     

Chemical polymorphism of essential oil in Thymus praecox ssp. arcticus (Lamiaceae) from Greenland

The chemistry of the essential oil of Thymus praecox Opiz ssp. arcticus (E. Durand) Jalas from Greenland was studied with the intention of comparing it with the results obtained earlier from Icelandic material. All the 17 samples collected at different localities of South–West Greenland were found to contain linalyl acetate as main component besides some sesquiterpene hydrocarbons and some oxygenated sesquiterpenes. The variable content of the sesquiterpene alcohols, nerolidol and hedycaryol in the essential oil gave reason to define four different chemotypes. The pattern of the chemotype characterizing compounds was identical with that of four of the seven chemotypes found earlier to be the most widely distributed in Iceland, namely chemotypes B, C, D, and F. No correlation between the occurrence of a certain type and special environmental conditions was found. That the essential oil chemistry and the appearance of polychemism in the Greenland Thymus plants accords so well with that of the Icelandic ones, indicates that the distance of nearly 300 km between Iceland and Greenland has not led to locally limited "chemical races" within Thymus praecox ssp. arcticus. These findings are contrary to the results obtained in some Mediterranean Thymus species.     

Genetic analysis of population structure of tusk in the North Atlantic

To study the population structure of tusk Brosme brosme in the North Atlantic, samples from six fishing grounds were collected: St Kilda; Storegga; Faroe Islands; Rockall bank; Davis Strait and East Greenland. In addition two samples from the Norwegian coast; Kragerø and Øygarden, were included. Nine enzymes and haemoglobin were analysed by starch gel and agar gel electrophoresis. In addition isoelectric focusing (IEF) was carried out. At least 22 loci were represented. Polymorphisms were shown in eight loci and average heterozygosity was found to be about 0.05. Highest heterozygosity was found in haemoglobin analysed by Smithies buffer pH 8.6. Malate dehydrogenase ( MDH-2 ) analysed in IEF (pH 3.5-9.5), and haemoglobin were found as valuable tools for studies of stock structure in tusk. In the Greenland samples only one of the MDH-2 heterozygotes was found, while in the East Atlantic both the observed heterozygotes were more frequent. The frequencies of the the Hb * b allele were about 0.40 and 0.70 in the samples from east and west Atlantic respectively.     

Living on the good soil: relationships between soils,vegetation and human settlement during the late Allerød period in Denmark

The immigration of woody plants, especially Betula (tree birch), is examined in relation to geomorphological regions in a compilation of Late-glacial plant macrofossil records from Denmark. The immigration of trees led to a large ecological transformation of the landscape and had a major effect on the flora and fauna available to Palaeolithic people. We show that soil type was a controlling factor in the development of vegetation during the Allerød and Younger Dryas periods. Following the first immigration of trees during the Allerød period, woods became established in the eastern part of Denmark, where ice advances from the Baltic had deposited calcareous and clayey sediments. The western and northern parts of Denmark that are characterised by more sandy and non-calcareous sediments remained treeless throughout the whole Late-glacial period. Finds from the Bromme Culture are concentrated in the region which was wooded, suggesting that the regional variable environment allowed local adaptations using the diverse resources available.     

Actual and potential tree-line in the North Atlantic region,especially in Greenland and the Faroes

Betula pubescens Ehrh. s.l. is the only forest-forming tree-species which has spread naturally to Iceland and southwesternmost Greenland. No trees have immigrated naturally to the Faroe Isles. Afforestation experiments and gardening have resulted in successful introduction of several tree species. Recent experiments comprise planting of Rocky Mountains tree-line species in SW-Greenland northward to Søndre Strømfjord (67°N), and the introduction to the Faroe Isles (62°N) of trees and shrubs from cool temperate forests of the southern hemisphere, e.g. Nothofagus spp. and Embothrium coccineum Forst. (Proteaceae).     

Analysis of Clostridium botulinum serotype E strains by using multilocus sequence typing, amplified fragment length polymorphism, variable-number tandem-repeat analysis, and botulinum neurotoxin gene sequencing

A total of 41 Clostridium botulinum serotype E strains from different geographic regions, including Canada, Denmark, Finland, France, Greenland, Japan, and the United States, were compared by multilocus sequence typing (MLST), amplified fragment length polymorphism (AFLP) analysis, variable-number tandem-repeat (VNTR) analysis, and botulinum neurotoxin (bont) E gene sequencing. The strains, representing environmental, food-borne, and infant botulism samples collected from 1932 to 2007, were analyzed to compare serotype E strains from different geographic regions and types of botulism and to determine whether each of the strains contained the transposon-associated recombinase rarA, involved with bont/E insertion. MLST examination using 15 genes clustered the strains into several clades, with most members within a cluster sharing the same BoNT/E subtype (BoNT/E1, E2, E3, or E6). Sequencing of the bont/E gene identified two new variants (E7, E8) that showed regions of recombination with other E subtypes. The AFLP dendrogram clustered the 41 strains similarly to the MLST dendrogram. Strains that could not be differentiated by AFLP, MLST, or bont gene sequencing were further examined using three VNTR regions. Both intact and split rarA genes were amplified by PCR in each of the strains, and their identities were confirmed in 11 strains by amplicon sequencing. The findings suggest that (i) the C. botulinum serotype E strains result from the targeted insertion of the bont/E gene into genetically conserved bacteria and (ii) recombination events (not random mutations) within bont/E result in toxin variants or subtypes within strains.     

No Nation Is an Island: Language, Culture, and National Identity in the Faroe Islands

No Nation Is an Island: Language, Culture, and National Identity in the Faroe Islands. Tom Nauerby. North Atlantic Monographs, 3. Århus, Denmark: SNAI-North Atlantic Publications; distributed by Arhus University Press, 1996. 237 pp.     

Clostridium botulinum in the soil of Paraguay

Seventeen soil samples of Paraguay were examined for the presence of Clostridium botulinum. Botulinum type A, C1 and F toxins were detected in soil cultures. Type E toxin was not detected in any of soil cultures including those from river and lake shores.