Gudni A. Alfredsson

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We describe the observed relationship of campylobacter in poultry operations to human cases in a closed environment. During 1999 in Iceland, domestic cases of campylobacteriosis reached peak levels at 116/100,000 and in 2000 dropped to 33/100,000. Approximately 62% of broiler carcass rinses were contaminated with Campylobacter spp. in 1999. During 2000,(More)
Thermophilic obligately autotrophic hydrogen-oxidizing bacteria were isolated from several alkaline hot springs in Iceland. The bacteria were Gram negative rods, 0.4–0.5 μm in diameter and 3–4 μm long but 6–7 μm long cells without septa were often seen. Long and short laments are formed. Spores, flagella or lipid granules were not observed. Strains H1 and(More)
An extracellular serine proteinase purified from cultures of a psychrotrophic Vibrio species (strain PA-44) belongs to the proteinase K family of the superfamily of subtilisin-like proteinases. The enzyme is secreted as a 47-kDa protein, but under mild heat treatment (30 min at 40 degrees C) undergoes autoproteolytic cleavage on the carboxyl-side of the(More)
Thermophilic, aerobic bacteria of the genus Thermus were isolated from submarine alkaline hot springs in Iceland. Five submarine hot springs were sampled, and all had viable counts of Thermus spp. of about 10 CFU/ml. All submarine strains grew in the presence of NaCl at 3% or higher, but no strains from terrestrial hot springs would grow at concentrations(More)
The sour dough bread making process is extensively used to produce wholesome palatable rye bread. The process is traditionally done using a back-slopping procedure. Traditional sour doughs in Finland comprise of lactic acid bacteria and yeasts. The yeasts present in these doughs have been enriched in the doughs due to their metabolic activities, e.g. acid(More)
The growth range in nature of bacteria belonging to the genus Thermus was investigated by sampling 55 different hot springs in Iceland. The springs ranged in temperature from 32 to 99 degrees C, and in pH from 2.1 to 10.1. Viable counts of Thermus spp. ranging from 10 to 10 CFU/100 ml of spring water were found in 27 of the springs sampled. The temperature(More)
The gene encoding alanine dehydrogenase (AlaDH; EC from the marine psychrophilic bacterium strain PA-43 was cloned, sequenced, and overexpressed in Escherichia coli. The primary structure was deduced on the basis of the nucleotide sequence. The enzyme subunit contains 371 amino acid residues, and the sequence is 90% and 77% identical,(More)
A new, two-tier system for biotyping Salmonella typhimurium gives a finer and more reliable differentiation of strains than the Kristensen scheme and is capable of future extension by the addition of new types and new tests. Strains are allocated to a primary type (1-32) by their reactions in five primary tests with Bitter's xylose medium, meso-inositol,(More)
An extracellular serine peptidase, purified from the culture supernatant of the sub-Arctic psychrophilic bacterium strain PA-43, is monomeric, with a relative molecular mass of 76000, and an unusually low pI of 3.8. The peptidase is active towards N-succinyl AAPF p-nitroanilide and N-succinyl AAPL p-nitroanilide, indicating a chymotrypsin-like substrate(More)
Incurred samples from a pig treated with sulphamethazine and spiked samples of the same concentration were compared during frozen storage. The contents of sulphamethazine in the different types of samples decreased similarly to about 50% after 15 months. When the samples were heat treated before analysis the sulphamethazine concentration did not change over(More)