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31 results on '"Zajicek, James L."'

2. Paenibacillus thiaminolyticus is not the cause of thiamine deficiency impeding lake trout (Salvelinus namaycush) recruitment in the Great Lakes

Author

Richter, Catherine A., Evans, Allison N., Wright-Osment, Maureen K., Zajicek, James L., Heppell, Scott A., Riley, Stephen C., Krueger, Charles C., and Tillitt, Donald E.

Subjects
Great Lakes (North America) -- Environmental aspects, Gram-positive bacteria -- Health aspects, Lake trout -- Diseases -- Care and treatment, Vitamin B1 deficiency -- Diagnosis -- Care and treatment, Earth sciences
Abstract

Thiamine (vitamin [B.sub.1]) deficiency is a global concern affecting wildlife, livestock, and humans. In Great Lakes salmonines, thiamine deficiency causes embryo mortality and is an impediment to restoration of native lake trout (Salvelinus namaycush) stocks. Thiamine deficiency in fish may result from a diet of prey with high levels of thiaminase I. The discoveries that the bacterial species Paenibacillus thiaminolyticus produces thiaminase I, is found in viscera of thiaminase- containing prey fish, and causes mortality when fed to lake trout in the laboratory provided circumstantial evidence implicating P. thiaminolyticus. This study quantified the contribution of P. thiaminolyticus to the total thiaminase I activity in multiple trophic levels of Great Lakes food webs. Unexpectedly, no relationship between thiaminase activity and either the amount of P. thiaminolyticus thiaminase I protein or the abundance of P. thiaminolyticus cells was found. These results demonstrate that P. thiaminolyticus is not the primary source of thiaminase activity affecting Great Lakes salmonines and calls into question the long-standing assumption that P. thiaminolyticus is the source of thiaminase in other wild and domestic animals. La carence en thiamine (vitamine [B.sub.1]) est un probleme d'envergure planetaire touchant tant les animaux sauvages et d'elevage que les humains. Chez les salmonines des Grands Lacs, la carence en thiamine est cause de mortalite embryonnaire et entrave le retablissement des stocks indigenes de touladi (Salvelinus namaycush). Une carence en thiamine chez les poissons peut decouler d'une alimentation faite des proies avec de fortes teneurs en thiaminase I. Le fait que la bacterie Paenibacillus thiaminolyticus produit de la thiaminase I, qu' elle est presente dans les visceres de poissons proies contenant de la thiaminase et qu'elle cause une mortalite quand elle est donnee a manger a des touladis en laboratoire sont autant de decouvertes offrant des preuves circonstancielles de l'implication de P. thiaminolyticus. L'etude a quantifie la contribution de P. thiaminolyticus al' activite totale de la thiaminase I dans de multiples niveaux trophiques de reseaux trophiques des Grands Lacs. Contre toute attente, aucun lien n'a ete observe entre l'activite de la thiaminase et la quantite de proteine thiaminase I de P. thiaminolyticus ou l'abondance de cellules de P. thiaminolyticus. Ces resultats demontrent que P. thiaminolyticus n'est pas la principale source d'activite de la thiaminase affectant les salmonines des Grands Lacs et remet en question le postulat bien etabli voulant que P. thiaminolyticus soit la source de la thiaminase dans d autres animaux sauvages ou domestiques. [Traduit par la Redaction], Introduction Thiamine (vitamin B1) is an essential nutrient that is required for carbohydrate metabolism and neural function. Thiamine deficiency causes adverse effects in fish (Brown et al. 2005), wildlife (Balk [...]

Published
2012
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5. Thiamine concentrations in lake trout and Atlantic salmon eggs during 14 years following the invasion of alewife in Lake Champlain

Author

Ladago, Bret J., primary, Futia, Matthew H., additional, Ardren, William R., additional, Honeyfield, Dale C., additional, Kelsey, Kevin P., additional, Kozel, Carrie L., additional, Riley, Stephen C., additional, Rinchard, Jacques, additional, Tillitt, Donald E., additional, Zajicek, James L., additional, and Marsden, J. Ellen, additional

Published
2020
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6. Characterization of dietary exposure to planar halogenated hydrocarbons, dioxin equivalents, and biomagnification

Author

Tillitt, Donald E., Gale, Robert W., Meadows, John C., Zajicek, James L., Peterman, Paul H., Heaton, Silvia N., Jones, Paul D., Bursian, Steven J., Kubiak, Timothy J., Giesy, John P., and Aulerich, Richard J.

Subjects
Minks -- Food and nutrition, Animals -- Food and nutrition, Animal food -- Contamination, Reproductive toxicology -- Research, Environmental issues, Science and technology
Abstract

Minks are among the most sensitive mammalian species to the reproductive toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin and related compounds. This was confirmed by a study of the chemical characterization of the diets and the adult mink livers. An additive model of toxicity was compared with the results of the H4IIE bioassay on samples of their diets and livers. Dioxin-like potency of the planar halogenated hydrocarbon (PHH) mixtures mostly followed an additive model of toxicity. Dietary and liver tissue-based threshold concentrations for reproductive toxicity in mink were consistent regardless of whether PHHs were quantified as additive toxicity or H4IIE bioassay.

Published
1996

17. Effectiveness of Egg Immersion in Aqueous Solutions of Thiamine and Thiamine Analogs for Reducing Early Mortality Syndrome

Author

Brown, Scott B., primary, Brown, Lisa R., additional, Brown, Mitra, additional, Moore, Kristin, additional, Villella, Maria, additional, Fitzsimons, John D., additional, Williston, Bill, additional, Honeyfield, Dale C., additional, Hinterkopf, Joy P., additional, Tillitt, Donald E., additional, Zajicek, James L., additional, and Wolgamood, Martha, additional

Published
2005
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21. Can Diet-Dependent Factors Help Explain Fish-to-Fish Variation in Thiamine-Dependent Early Mortality Syndrome?

Author

Brown, Scott B., primary, Arts, Michael T., additional, Brown, Lisa R., additional, Brown, Mitra, additional, Moore, Kristin, additional, Villella, Maria, additional, Fitzsimons, John D., additional, Honeyfield, Dale C., additional, Tillitt, Donald E., additional, Zajicek, James L., additional, Wolgamood, Martha, additional, and Hnath, John G., additional

Published
2005
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24. Dietary Exposure of Mink to Carp from Saginaw Bay. 3. Characterization of Dietary Exposure to Planar Halogenated Hydrocarbons, Dioxin Equivalents, and Biomagnification

Author

Tillitt, Donald E., primary, Gale, Robert W., additional, Meadows, John C., additional, Zajicek, James L., additional, Peterman, Paul H., additional, Heaton, Silvia N., additional, Jones, Paul D., additional, Bursian, Steven J., additional, Kubiak, Timothy J., additional, Giesy, John P., additional, and Aulerich, Richard J., additional

Published
1995
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27. Variations of Thiaminase I Activity pH Dependencies among Typical Great Lakes Forage Fish and Paenibacillus thiaminolyticus

Author

Zajicek, James L., Brown, Lisa, Brown, Scott B., Honeyfield, Dale C., Fitzsimons, John D., and Tillitt, Donald E.

Abstract

The source of thiaminase in the Great Lakes food web remains unknown. Biochemical characterization of the thiaminase I activities observed in forage fish was undertaken to provide insights into potential thiaminase sources and to optimize catalytic assay conditions. We measured the thiaminase I activities of crude extracts from five forage fish species and one strain of Paenibacillus thiaminolyticusover a range of pH values. The clupeids, alewife Alosa pseudoharengusand gizzard shad Dorosoma cepedianum, had very similar thiaminase I pH dependencies, with optimal activity ranges (=90% of maximum activity) between pH 4.6 and 5.5. Rainbow smelt Osmerus mordaxand spottail shiner Notropis hudsoniushad optimal activity ranges between pH 5.5–6.6. The thiaminase I activity pH dependence profile of P. thiaminolyticushad an optimal activity range between pH 5.4 and 6.3, which was similar to the optimal range for rainbow smelt and spottail shiners. Incubation of P. thiaminolyticusextracts with extracts from bloater Coregonus hoyi(normally, bloaters have little or no detectable thiaminase I activity) did not significantly alter the pH dependence profile of P. thiaminolyticus–derived thiaminase I, such that it continued to resemble that of the rainbow smelt and spottail shiner, with an apparent optimal activity range between pH 5.7 and 6.6. These data are consistent with the hypothesis of a bacterial source for thiaminase I in the nonclupeid species of forage fish; however, the data also suggest different sources of thiaminase I enzymes in the clupeid species.

Published
2009
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28. Quantitative Polymerase Chain Reaction (PCR) Assays for a Bacterial Thiaminase I Gene and the Thiaminase-Producing Bacterium Paenibacillus thiaminolyticus

Author

Richter, Catherine A., Wright-Osment, Maureen K., Zajicek, James L., Honeyfield, Dale C., and Tillitt, Donald E.

Abstract

The thiaminase I enzyme produced by the gram-positive bacterium Paenibacillus thiaminolyticusisolated from the viscera of Lake Michigan alewives Alosa pseudoharengusis currently the only defined source of the thiaminase activity linked to thiamine (vitamin B1) deficiency in early mortality syndrome (EMS) in the larvae of Great Lakes salmonines. Diets of alewife or isolated strains of P. thiaminolyticusmixed in a semipurified diet and fed to lake trout Salvelinus namaycushhave been shown to produce EMS in fry. We utilized quantitative polymerase chain reaction (Q-PCR) to aid in studies of the sources of P. thiaminolyticusand thiaminase I. Quantitative PCR assays were established to detect the thiaminase I gene of P. thiaminolyticus, the 16S rRNA gene from most species of bacteria, and the 16S rRNA gene specifically from P. thiaminolyticusand a few closely related taxa. The Q-PCR assays are linear over at least six orders of magnitude and can detect the thiaminase I gene of P. thiaminolyticusfrom as few as 1,000 P. thiaminolyticuscells/g of sample or the Paenibacillus16S rRNA gene from as few as 100 P. thiaminolyticuscells/g of sample. The initial results from alewife viscera samples with high thiaminase activity yielded unexpectedly low densities of P. thiaminolyticuscells; Paenibacillus thiaminolyticuswas detectable in 2 of 6 alewife viscera tested at densities on the order of 100 cells/g out of 100,000,000 total bacterial cells/g. The low numbers of P. thiaminolyticusdetected suggest that alewives contain additional non–P. thiaminolyticussources of thiaminase activity.

Published
2009
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29. TanA: a fluorogenic probe for thiaminase activityElectronic supplementary information (ESI) available: Experimental details. See DOI: 10.1039/c2ay26047

Author

Zhu, Wanjun, Zajicek, James L., Tillitt, Donald E., and Glass, Timothy E.

Abstract

A fluorogenic thiamine analogue is presented as a fluorescent probe for thiaminase activity. The emission of the fluorophore is quenched by photoinduced electron transfer (PET) to the N-substituted pyridinium portion of the probe. Action of the enzyme releases the free pyridine group causing a substantial increase in fluorescence.

Published
2012
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