Construction and Characterization of Chimeric Proteins Composed of Type-1 and Type-2 Periplasmic Binding Proteins MglB and ArgT

2004 ◽  
Vol 68 (4) ◽  
pp. 808-813 ◽  
Author(s):  
Kenji KASHIWAGI ◽  
Kaoru FUKAMI-KOBAYASHI ◽  
Kiyotaka SHIBA ◽  
Ken NISHIKAWA
2005 ◽  
Vol 35 (11) ◽  
pp. 2589-2602 ◽  
Author(s):  
Ryan J Hooper ◽  
K Sivasithamparam

Crown decline of wandoo, Eucalyptus wandoo, in southwest Western Australia has escalated over the last 10 years, so very few unaffected stands remain. To assess the canopy-damage characteristics of trees in decline a destructive, partial-harvest method was used to sample branches in natural mixed-age stands. Necrosis of common cankers was closely associated with type-1 borer damage, characterized by "longitudinal" gallery structure on declining trees only. Cankers were found to be consistently more severe on declining trees, with decay regions affecting a greater proportion of sapwood tissue. Several infestations causing type-1 borer damage that varied in age were found on declining branches, providing evidence of cyclical damage events. Type-2 borer damage characterized by "ring-barking" gallery structure caused extensive damage in canopies, but was not always associated with decline. Interactions between foliage density and canker score showed that 17.8% and 63.1% of the variability in foliage-density ratios was accounted for in declining intermediate-health and unhealthy classes, respectively. The relationship was negligible for the healthy class (9.9%), providing strong evidence that cankers are causing foliage loss in declining canopies. Evidence suggests that an interaction between type-1 borer infestations and decay-causing fungi is responsible for the decline in E. wandoo wandoo canopies.


1999 ◽  
Vol 181 (8) ◽  
pp. 2323-2329 ◽  
Author(s):  
Miguel Prudêncio ◽  
Robert R. Eady ◽  
Gary Sawers

ABSTRACT The nirA gene encoding the blue dissimilatory nitrite reductase from Alcaligenes xylosoxidans has been cloned and sequenced. To our knowledge, this is the first report of the characterization of a gene encoding a blue copper-containing nitrite reductase. The deduced amino acid sequence exhibits a high degree of similarity to other copper-containing nitrite reductases from various bacterial sources. The full-length protein included a 24-amino-acid leader peptide. The nirA gene was overexpressed inEscherichia coli and was shown to be exported to the periplasm. Purification was achieved in a single step, and analysis of the recombinant Nir enzyme revealed that cleavage of the signal peptide occurred at a position identical to that for the native enzyme isolated from A. xylosoxidans. The recombinant Nir isolated directly was blue and trimeric and, on the basis of electron paramagnetic resonance spectroscopy and metal analysis, possessed only type 1 copper centers. This type 2-depleted enzyme preparation also had a low nitrite reductase enzyme activity. Incubation of the periplasmic fraction with copper sulfate prior to purification resulted in the isolation of an enzyme with a full complement of type 1 and type 2 copper centers and a high specific activity. The kinetic properties of the recombinant enzyme were indistinguishable from those of the native nitrite reductase isolated from A. xylosoxidans. This rapid isolation procedure will greatly facilitate genetic and biochemical characterization of both wild-type and mutant derivatives of this protein.


2019 ◽  
Vol 40 (6) ◽  
pp. 1500-1520 ◽  
Author(s):  
Miriam S Udler ◽  
Mark I McCarthy ◽  
Jose C Florez ◽  
Anubha Mahajan

Abstract During the last decade, there have been substantial advances in the identification and characterization of DNA sequence variants associated with individual predisposition to type 1 and type 2 diabetes. As well as providing insights into the molecular, cellular, and physiological mechanisms involved in disease pathogenesis, these risk variants, when combined into a polygenic score, capture information on individual patterns of disease predisposition that have the potential to influence clinical management. In this review, we describe the various opportunities that polygenic scores provide: to predict diabetes risk, to support differential diagnosis, and to understand phenotypic and clinical heterogeneity. We also describe the challenges that will need to be overcome if this potential is to be fully realized.


Author(s):  
Benjamin Assad Jaghutriz ◽  
Robert Wagner ◽  
Stephanie Kullmann ◽  
Louise Fritsche ◽  
Sabine S. Eckstein ◽  
...  

AbstractPrevalence of both type 1 and type 2 diabetes mellitus is growing worldwide and one major cause for morbidity and mortality. However, not every patient develops diabetes-related complications, but causes for the individual susceptibility are still not fully understood. As a platform to address this, we initiated the TUDID (TUebingen DIabetes Database) study, a prospective, monocentric, observational study that includes adults with diabetes mellitus who are treated in the inpatient clinic of a University Hospital in southern Germany. Besides a thorough clinical examination and extensive laboratory tests (with integrated biobanking), major study focuses are the kidneys, the eyes, the vasculature as well as cognition and mood where standardized investigations for early stages for diabetes complications are performed. Analyses of the data generated by this precise characterization of diabetes-related complications will contribute to our understanding of the development and course of such complications, and thus facilitate the implementation of tailored treatment options that can reduce the risk and severity of diabetes-related complications.


1998 ◽  
Vol 20 (1) ◽  
pp. 99-110 ◽  
Author(s):  
FM Rogerson ◽  
J Courtemanche ◽  
A Fleury ◽  
JG LeHoux ◽  
JI Mason ◽  
...  

Western blot analyses of various hamster tissues reveal high levels of expression of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) in adrenal and liver, and moderate levels of expression in kidney. The expression in liver is sexually dimorphic; very high levels of protein are observed in adult male liver but very low levels are seen in the female liver. Three distinct cDNAs encoding isoforms of 3 beta-HSD were isolated from hamster cDNA libraries. The type 1 isoform is a high-affinity dehydrogenase/isomerase expressed in adrenal and male kidney. The type 2 isoform is also a high-affinity dehydrogenase/isomerase expressed in kidney and male liver. The type 3 enzyme is a 3-ketosteroid reductase expressed predominantly in kidney. Sequencing of the clones showed that all three are structurally very similar, although types 1 and 2 share the greatest degree of similarity. Immunohistochemical staining for 3 beta-HSD in the adrenal was found throughout the adrenal cortex. In the kidney staining was confined to tubules, and in the liver, heavy staining was found in hepatocytes. The cloning of cDNAs for 3 beta-HSD from the liver and kidney should help in elucidating the function of this enzyme in these tissues.


2005 ◽  
Vol 21 (4) ◽  
pp. 249-255 ◽  
Author(s):  
Ana Filipa Silva ◽  
Catarina Almeida ◽  
Helena Cortes Martins ◽  
Rodrigo Coutinho ◽  
Emília Leitão ◽  
...  

2015 ◽  
Vol 81 (21) ◽  
pp. 7553-7559 ◽  
Author(s):  
Nidhi Shrivastava ◽  
Zbynek Prokop ◽  
Ashwani Kumar

ABSTRACTLinA is the first enzyme of the microbial degradation pathway of a chlorinated insecticide, hexachlorocyclohexane (HCH), and mediates the dehydrochlorination of α-, γ-, and δ-HCH. Its two variants, LinA type 1 and LinA type 2, which differ at 10 out of 156 amino acid residues, have been described. Their activities for the metabolism of different HCH isomers differ considerably but overall are high for γ-HCH, moderate for α-HCH, low for δ-HCH, and lacking for β-HCH. Here, we describe the characterization of a new variant of this enzyme, LinA type 3, whose gene was identified from the metagenome of an HCH-contaminated soil sample. Its deduced primary structure in the region spanning amino acid residues 1 to 147 of the protein exhibits 17 and 12 differences from LinA type 1 and LinA type 2, respectively. In addition, the residues GIHFAPS, present at the region spanning residues 148 to 154 in both LinA type 1 and LinA type 2, are deleted in LinA type 3.The activity of LinA type 3 for the metabolism of δ-HCH is several orders of magnitude higher than that of LinA type 1 or LinA type 2 and can be useful for improvement of the metabolism of δ-HCH.


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