scholarly journals Identification of Three Monofunctional Diterpene Synthases with Specific Enzyme Activities Expressed during Heartwood Formation in Western Redcedar (Thuja plicata) Trees

Plants ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1018 ◽  
Author(s):  
Sifat Tasnim ◽  
Regine Gries ◽  
Jim Mattsson
Keyword(s):  
Active Sites ◽  
Genetically Engineered ◽  
Thuja Plicata ◽  
Heartwood Formation ◽  
Important Species ◽  
Western Redcedar ◽  
Specialized Metabolites ◽  
Catalytic Activities ◽  
High Incidence ◽  
Diterpene Synthases

Upon harvest, Western redcedar (WRC; Thuja plicata) trees have a high incidence and extent of heartwood rot. While monoterpenoids and lignans have been linked to rot resistance in this species, other specialized metabolites, such as diterpenes, are likely to contribute to rot resistance. Here we report the cloning and functional assessment of three putative diterpene synthase (TpdiTPS) genes expressed during heartwood formation in WRC. The predicted proteins of the three genes lack either of the two catalytically independent active sites typical of most diTPS, indicating monofunctional rather than bifunctional activity. To identify potential catalytic activities of these proteins, we expressed them in genetically engineered Escherichia coli strains that produce four potential substrates, geranylgeranyl diphosphate (GGDP), ent, syn, and normal stereoisomers of copalyl diphosphate (CDP). We found that TpdiTPS3 used GGDP to produce CDP. TpdiTPS2 used normal CDP to produce levopimaradiene. TpdiTPS1 showed stereoselectivity as it used normal CDP to produce sandaracopimaradiene and syn-CDP to produce syn-stemod-13(17)-ene. These genes and protein enzymatic activities have not been previously reported in WRC and provide an opportunity to assess their potential roles in heartwood rot resistance in this economically important species.

scholarly journals One-Step Hydrothermal Synthesis of P25 @ Few Layered MoS2 Nanosheets toward Enhanced Bi-catalytic Activities: Photocatalysis and Electrocatalysis

Nanomaterials ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1636 ◽  
Author(s):  
Zhou ◽  
Zhang ◽  
Wang ◽  
Wang ◽  
Xu ◽  
...  
Keyword(s):  
Hydrothermal Synthesis ◽  
Active Sites ◽  
Photocatalytic Performance ◽  
Transformation Efficiency ◽  
Hydrothermal Process ◽  
Mos2 Nanosheets ◽  
Sunlight Irradiation ◽  
Catalytic Activities ◽  
One Step ◽  
Layered Mos2

P25 loaded few layered molybdenum disulfide (MoS2) nanosheets (P25@MoS2) are successfully synthesized through a facile one-step hydrothermal process. The bi-catalytic activities, i.e., photocatalytic and electrocatalytic activities, of the as-prepared nanomaterials have been investigated. For the as-prepared products, the photocatalytic performances were investigated by degrading simulated pollutant under sunlight irradiation, and the hydrogen evolution reaction evaluated the electrocatalytic performances. The results indicate that P25@MoS2 possesses excellent activities in both photocatalysis and electrocatalysis. The presence of MoS2 broadens the light absorption range of P25 and improves the separation and transformation efficiency of photogenerated carriers, thus improving its photocatalytic performance. The existence of P25 inhibits the aggregation of MoS2 to form more dispersed MoS2 nanosheets with only few layers increasing its active sites. Thereby, the electrocatalytic performance is heightened. The excellent multifunction makes the as-prepared P25@MoS2 a promising material in the fields of environment and energy.

The mating system in natural populations of western redcedar (Thuja plicata)

2001 ◽  
Vol 79 (6) ◽  
pp. 753-756 ◽  
Author(s):  
Lisa M. O'Connell ◽  
Frédérique Viard ◽  
John Russell ◽  
Kermit Ritland
Keyword(s):  
Mating System ◽  
Natural Populations ◽  
Thuja Plicata ◽  
Western Redcedar

scholarly journals In-Exchanged CHA Zeolites for Selective Dehydrogenation of Ethane: Characterization and Effect of Zeolite Framework Type

Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 807
Author(s):  
Zen Maeno ◽  
Xiaopeng Wu ◽  
Shunsaku Yasumura ◽  
Takashi Toyao ◽  
Yasuharu Kanda ◽  
...  
Keyword(s):  
Active Sites ◽  
Temperature Programmed Desorption ◽  
X Ray Diffraction ◽  
Zeolite Framework ◽  
X Ray ◽  
Catalytic Activities ◽  
Ethane Dehydrogenation ◽  
Temperature Programmed

In this study, the characterization of In-exchanged CHA zeolite (In-CHA (SiO2/Al2O3 = 22.3)) was conducted by in-situ X-ray diffraction (XRD) and ammonia temperature-programmed desorption (NH3-TPD). We also prepared other In-exchanged zeolites with different zeolite structures (In-MFI (SiO2/Al2O3 = 22.3), In-MOR (SiO2/Al2O3 = 20), and In-BEA (SiO2/Al2O3 = 25)) and different SiO2/Al2O3 ratios (In-CHA(Al-rich) (SiO2/Al2O3 = 13.7)). Their catalytic activities in nonoxidative ethane dehydrogenation were compared. Among the tested catalysts, In-CHA(Al-rich) provided the highest conversion. From kinetic experiments and in-situ Fourier transform infrared (FTIR) spectroscopy, [InH2]+ ions are formed regardless of SiO2/Al2O3 ratio, serving as the active sites.

Ectomycorrhizal mushroom response to partial cutting in a western hemlock - western redcedar forest

2001 ◽  
Vol 31 (6) ◽  
pp. 978-987 ◽  
Author(s):  
J M Kranabetter ◽  
P Kroeger
Keyword(s):  
Stand Structure ◽  
Basal Area ◽  
Tsuga Heterophylla ◽  
Western Hemlock ◽  
Thuja Plicata ◽  
Soil Conditions ◽  
Taxon Richness ◽  
Partial Cutting ◽  
Western Redcedar ◽  
Significant Block

We examined epigeous ectomycorrhizal mushroom richness and productivity after partial cutting in a western hemlock (Tsuga heterophylla (Raf.) Sarg.) - western redcedar (Thuja plicata Donn ex D. Don in Lamb.) forest of northwestern British Columbia. Mushrooms were collected throughout the fruiting season (July to October) for 3 years, starting 5 years after partial cutting, from plots with mesic soil conditions and residual basal areas ranging from 23 to 69 m2/ha for western hemlock and 0 to 26 m2/ha for western redcedar. Partial cutting had no apparent effect on mushroom phenology over the 3 years. Significant block interactions demonstrated that reductions in basal area of western hemlock could lead to positive, neutral, and negative responses in mushroom richness, biomass, and number of fruiting bodies. These responses were related to stand structure and the potential differences in tree vigour after partial cutting. In addition, there was weak evidence that western redcedar, a host for vesicular-arbuscular mycorrhiza, had a negative effect on average taxon richness. The study demonstrated that partial-cutting systems could allow some timber removal without necessarily reducing ectomycorrhizal mushroom communities.

scholarly journals Aldehyde dehydrogenase. An enzyme with two distinct catalytic activities at a single type of active site

1985 ◽  
Vol 230 (1) ◽  
pp. 261-267 ◽  
Author(s):  
R J Duncan
Keyword(s):  
Aldehyde Dehydrogenase ◽  
Active Site ◽  
Active Sites ◽  
Catalytic Site ◽  
Single Type ◽  
Catalytic Activities ◽  
Binding Domains

The evidence for and against the esterase and dehydrogenase active sites of aldehyde dehydrogenase being topologically distinct is examined. It is found that all the evidence (including all that previously amassed by others in favour of distinct binding domains) is actually consistent with, and in favour of, a single type of catalytic site having both activities. The existence of separate high-Km modulating sites for the enzyme is also questioned.

Feeding biology of Caranx bucculentus Alleyne and Maclay (Teleostei: Carangidae) in Albatross Bay, Gulf of Carpentaria, with special reference to predation on penaeid prawns

1989 ◽  
Vol 40 (6) ◽  
pp. 657 ◽  
Author(s):  
DT Bewer ◽  
SJM Blaber ◽  
JP Salini
Keyword(s):  
Seasonal Variation ◽  
Special Reference ◽  
Dry Weight ◽  
Important Species ◽  
Feeding Biology ◽  
High Incidence ◽  
Total Diet ◽  
Considerable Impact ◽  
Commercially Important ◽  
Diet Shifts

Caranx bucculentus is an abundant predator in the commercial prawn grounds of Albatross Bay in the Gulf of Carpentaria. The stomachs of samples taken from Albatross Bay contained mainly teleosts (48%) and crustaceans (46%), with commercially important prawns contributing 15% by dry weight to the total diet. The proportion of teleosts, penaeids, brachyurans, 'other crustaceans' and molluscs in the diet changes as the fish grow and their diet shifts from mainly crustaceans to mainly teleosts. Although the percentage of teleosts, penaeids, brachyurans and 'other crustaceans' eaten varied with the time of sampling, no seasonal variation was noted. Only the numbers of penaeids and 'other crustaceans' eaten varied significantly over 24 h. Caranx bucculentus less than 200 mm SL ate most penaeid prey during the day and primarily took small, commercially unimportant species. In contrast, fishes more than 275 mm long took larger, commercially important species, and mainly at night. The abundance of large C. bucculentus and the high incidence of commercial penaeids in their diet indicate that this species may have a considerable impact on the prawn resources of Albatross Bay.

Effects of leaching on fungal growth and decay of western redcedar

2009 ◽  
Vol 55 (5) ◽  
pp. 578-586 ◽  
Author(s):  
Russell J. Chedgy ◽  
Young Woon Lim ◽  
Colette Breuil
Keyword(s):  
Fungal Growth ◽  
Fungal Species ◽  
Heterobasidion Annosum ◽  
Thuja Plicata ◽  
Western Redcedar ◽  
Coniophora Puteana ◽  
Soil Block ◽  
Block Test ◽  
Thuja Plicata Donn

We tested the effect of leaching on the concentration of western redcedar (WRC; Thuja plicata Donn ex D. Don) heartwood extractives that are known to exhibit antimicrobial activity and correlated this with fungal growth and decay. We assessed the extractive tolerance of the following fungal species: Acanthophysium lividocaeruleum , Coniophora puteana , Heterobasidion annosum , Pachnocybe ferruginea , Phellinus sulphurascens , and Phellinus weirii by measuring their growth rate (mm/day) on media with or without WRC leachate. These data were correlated with the ability of the fungal species to grow on and decay leached versus nonleached WRC. We used an ergosterol assay to estimate growth and a standard soil-block test to assess decay. We estimated that leaching reduced the concentration of 5 major extractives: (–)-plicatic acid, β-thujaplicin, γ-thujaplicin, β-thujaplicinol, and thujic acid by ~80%. Phellinus sulphurascens exhibited the lowest extractive-tolerance in vitro, grew poorly on and caused minimal decay in nonleached WRC, but it grew well on and decayed pine and leached WRC. Coniophora puteana, H. annosum, and P. weirii displayed moderate to high tolerance to leachate, grew on and caused decay in nonleached as well as leached WRC, but their growth and decay were always greatest on leached WRC and pine, suggesting that leaching enhances decay by these fungi. Acanthophysium lividocaeruleum and Pachnocybe ferruginea exhibited high extractive-tolerance. Whereas A. lividocaeruleum clearly caused decay on all types of wood, no decay was observed with Pachnocybe ferruginea, which grew very slowly in the different wood species, and it may or may not be able to decay wood.

scholarly journals Stem Characteristics on the Lower Log of 35-Year-Old Western Redcedar Grown at Several Spacings

1997 ◽  
Vol 12 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Jeffrey D. DeBell ◽  
Barbara L. Gartner
Keyword(s):  
Large Diameter ◽  
Stem Diameter ◽  
Stem Length ◽  
Thuja Plicata ◽  
Western Redcedar ◽  
Branch Diameter ◽  
University Of British Columbia ◽  
The University ◽  
Number Of Branches

Abstract Information on stem characteristics of western redcedar (Thuja plicata) grown in managed stands is quite limited. Stem characteristics are important because they influence the quality of logs and lumber produced. We measured branch diameter, number of branches, taper, and fluting severity on the first 5m log of stems grown at spacings of 1.8 to 4.6 m in a 35-yr-old spacing trial on the University of British Columbia Research Forest. Average branch diameter increased from 15 mm to 25 mm as tree spacing increased from 1.8 m to 4.6 m. Number of branches per unit of stem length was unaffected by spacing. Trees at wider spacings tended to be more tapered and have more butt swell than those at narrower spacings. At wider spacings, more trees showed fluting, and that fluting was more severe than at narrower spacings. However, most trees had no fluting or only mild fluting even at the 4.6 m spacing. Branch diameter, taper, and fluting were all related to stem diameter. Smaller diameter stems tended to have smaller branches, less taper, and were less likely to have severe fluting than large diameter stems. Branch diameter was larger at wider spacings even for trees of the same stem diameter. West. J. Appl. For. 12(1):9-14.

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