Browsing by Author "Pettersson, U."

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Cloning and characterization of a repetitive DNA sequence specific for Wuchereria bancrofti
    (American Society of Tropical Medicine and Hygiene, 1994) Siridewa, K.; Karunanayake, E.H.; Chandrasekharan, N.V.; Abeyewickreme, W.; Franzen, L.; Aslund, L.; Pettersson, U.
    A genomic library constructed in a bacteriophage lambda replacement vector (EMBL3) with Wuchereria bancrofti DNA partially digested with Sau 3A I was screened with 32P-labeled W. bancrofti total DNA, and a strongly reactive recombinant, EMBL3Wb34, was isolated. This clone contained an approximately 16-kb insert that showed some cross-hybridization with Brugia malayi and B. pahangi DNA. However, a 969-bp subclone from EMBL3Wb34, designated pWb12, hybridized only with W. bancrofti DNA and was able to detect as little as 300 pg. Furthermore, pWb12 could detect DNA from a single infective larva or one microfilaria. It has a moderate copy number (450-700) and appears to be interspersed within the parasite genome. The nucleotide sequence contains 66% A+T and 34% G+C and shows no notable internal repeats.
  • No Thumbnail Available
    Item
    Dirofilaria repens: Cloning and Characterization of a Repeated DNA Sequence for the Diagnosis of Dirofilariasis in Dogs, Canis familiaris
    (Academic Press, 1994) Chandrasekharan, N.V.; Karunanayake, E.H.; Franzen, L.; Abeyewickreme, W.; Pettersson, U.
    A highly repetitive DNA element from the genome of the filarial nematode Dirofilaria repens has been cloned and sequenced. The 176-base pair repeating units are arranged in direct tandem and are clustered in the parasite genome. All repeats appear to belong to a single family although some elements have diverged significantly. The repeats are present in about 15,000 copies and constitute approximately 3.0% of the parasite genome. The cloned repetitive sequence hybridized only to D. repens DNA and was sensitive enough to detect 250 to 500 pg of D. repens DNA, a single microfilariae in infected blood samples, and a single third stage larvae in mosquitoes. The high specificity and sensitivity of the cloned fragment makes it ideal as a diagnostic probe for detecting D. repens in both the host and the vector.