F plasmid derivatives carrying kan insertion mutations in the transfer region genes traR, trbJ, and trbH were constructed. Standard tests indicated that these loci are not essential for F pilus production or F transfer among Escherichia coli K-12 hosts. Among the traR and trbH mutants tested, the orientation of the kan cassette had no effect on the mutant phenotype. In each case, there was no s...

The streptomycin (SM) gene cluster was investigated for its distribution in streptomycetes by Southern hybridization using nick-translated DNA probes, which were isolated from the SM-6-phosphotransferase (SPH) and amidinotransferase (ADT) regions of the SM gene cluster of Streptomyces griseus SS-1198. Bgl II-digested genomic DNAs from SM-producing strains of S. griseus yielded the same size fra...

Nutrient losses from agricultural land constitute an important part of the total flow of nutrient to lakes and seas in Sweden and the Baltic region. With the EU Directive on water, to be implemented shortly throughout Europe, the expectations on what can be achieved through the decentralisation of various responsibilities from authorities to groups in the civil society is increasing. An importa...

This paper involves categories and computer science. Gröbner basis theory is a branch of computer algebra which has been usefully applied to a wide range of problems. Kan extensions are a key concept of category theory capable of expressing most algebraic structures. The paper combines the two, using Gröbner basis techniques to compute certain kinds of Kan extension.

Spirochete periplasmic flagella (PFs), including those from Brachyspira (Serpulina), Spirochaeta, Treponema, and Leptospira spp., have a unique structure. In most spirochete species, the periplasmic flagellar filaments consist of a core of at least three proteins (FlaB1, FlaB2, and FlaB3) and a sheath protein (FlaA). Each of these proteins is encoded by a separate gene. Using Brachyspira hyodys...

iii

BACKGROUND Rapid molecular diagnostics for detecting multidrug-resistant and extensively drug-resistant tuberculosis (M/XDR-TB) primarily identify mutations in Mycobacterium tuberculosis (Mtb) genes associated with drug resistance. Their accuracy, however, is dependent largely on the strength of the association between a specific mutation and the phenotypic resistance of the isolate with that m...

Oxygenases are promising biocatalysts for performing selective hydroxylations not accessible by chemical methods. Whereas toluene 4-monooxygenase (T4MO) of Pseudomonas mendocina KR1 hydroxylates monosubstituted benzenes at the para position and toluene ortho-monooxygenase (TOM) of Burkholderia cepacia G4 hydroxylates at the ortho position, toluene 3-monooxygenase (T3MO) of Ralstonia pickettii P...

Introduction: Monitoring and controlling water resources and using health risk assessment approaches for water pollutants are essential for health promotion programs. This study aims to determine the water quality status and its spatiotemporal variation across the Kan River Basin, explore the interrelationship between surface and groundwater quality indices, and assess the nitrate health risk i...