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Natasha S. Vitek - One of the best experts on this subject based on the ideXlab platform.
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cretaceous soft shelled turtles trionychidae of mongolia new diversity records and a revision
Journal of Systematic Palaeontology, 2014Co-Authors: Igor G. Danilov, Ren Hirayama, Vladimir B. Sukhanov, Shigeru Suzuki, Mahito Watabe, Natasha S. VitekAbstract:This paper is devoted to the description and revision of material of Cretaceous soft-shelled turtles (Trionychidae) of Mongolia. It includes the description of seven trionychid species, six of which are new, and two new genera: the cyclanorbine Nemegtemys conflata gen. et sp. nov. from the Nemegt Formation (Maastrichtian), and the trionychines Gobiapalone breviplastra gen. et sp. nov. from the Nemegt and Barungoyot (Campanian) formations, G. orlovi from the Baynshire Formation (Cenomanian–Santonian), ‘Trionyx’ baynshirensis sp. nov. from the Baynshire Formation, ‘T.’ gilbentuensis sp. nov. from the Nemegt Formation, ‘T.’ gobiensis sp. nov. from the Nemegt Formation, and ‘T.’ shiluutulensis sp. nov. from an unknown formation (Campanian). In addition, one shell from the ?Baynshire Formation of Khermin Tsav is assigned to Gobiapalone sp. The type material of Amyda menneri is considered to be Trionychidae indet. and Amyda menneri to be a nomen dubium. Finally, we revise other available materials of Cretaceous...
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Cretaceous soft-shelled turtles (Trionychidae) of Mongolia: new diversity, records and a revision
2014Co-Authors: Igor G. Danilov, Ren Hirayama, Vladimir B. Sukhanov, Shigeru Suzuki, Mahito Watabe, Natasha S. VitekAbstract:This paper is devoted to the description and revision of material of Cretaceous soft-shelled turtles (Trionychidae) of Mongolia. It includes the description of seven trionychid species, six of which are new, and two new genera: the cyclanorbine Nemegtemys conflata gen. et sp. nov. from the Nemegt Formation (Maastrichtian), and the trionychines Gobiapalone breviplastra gen. et sp. nov. from the Nemegt and Barungoyot (Campanian) formations, G. orlovi from the Baynshire Formation (Cenomanian–Santonian), ‘Trionyx’ baynshirensis sp. nov. from the Baynshire Formation, ‘T.’ gilbentuensis sp. nov. from the Nemegt Formation, ‘T.’ gobiensis sp. nov. from the Nemegt Formation, and ‘T.’ shiluutulensis sp. nov. from an unknown formation (Campanian). In addition, one shell from the ?Baynshire Formation of Khermin Tsav is assigned to Gobiapalone sp. The type material of Amyda menneri is considered to be Trionychidae indet. and Amyda menneri to be a nomen dubium. Finally, we revise other available materials of Cretaceous trionychids from 45 localities in Mongolia. Nemegtemys conflata, if correctly assigned, is the earliest known member of Cyclanorbinae. The two species of the new genus Gobiapalone are included in two phylogenetic analyses of Trionychidae. In both analyses Gobiapalone is monophyletic. In the first analysis, Gobiapalone is placed within Apalonina. In the second analysis, Gobiapalone is sister to Apalonina. Thus, the results of both analyses show that Apalonina, which is a rather advanced and well-supported trionychid clade, or its closest sister taxon (stem-Apalonina), were present in the Late Cretaceous of Asia. These results suggest that most other supra-generic clades of modern trionychids had been established in Asia by the Late Cretaceous. That suggestion is supported by the discovery of a cyclanorbine Nemegtemys conflata in the Late Cretaceous of Mongolia. Finally we summarize the latest data on temporal and geographical distributions of Cretaceous Trionychidae of Asia and North America.http://zoobank.org/urn:lsid:zoobank.org:pub:921DA1C5-C4B2-463D-A49D-608024C6036A
Karen A. Jensen - One of the best experts on this subject based on the ideXlab platform.
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Cultural Exploitation of Freshwater Turtles in Sarawak, Malaysian Borneo
Chelonian Conservation and Biology, 2008Co-Authors: Karen A. Jensen, Indraneil DasAbstract:Abstract We investigated the cultural exploitation of nonmarine turtles in Sarawak State, Malaysia. Turtles are primarily used for food, and the Asian softshell turtle, Amyda cartilaginea, appears to be the most desirable species. Other local demands include the pet trade, which involves both local and exotic species of turtles.
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Dietary Observations on the Asian Softshell Turtle (Amyda cartilaginea) from Sarawak, Malaysian Borneo
Chelonian Conservation and Biology, 2008Co-Authors: Karen A. Jensen, Indraneil DasAbstract:ABSTRACT We examined the diet of Amyda cartilaginea from 2 localities in Sarawak: Loagan Bunut National Park and Balai Ringin. The most commonly found items in stomach contents, when using percentage frequency of occurrence, were plant material (77%) and unknown vertebrate parts (55%). Fecal analysis indicated similar results: plant material (100%), unknown vertebrate parts (84%), fish (69%), and unknown arthropods (62%). Results indicate that A. cartilaginea is an opportunistic omnivore.
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Ecology and use of Asian soft-shell turtle (Amyda cartilaginea) with notes on other species
2006Co-Authors: Karen A. JensenAbstract:Turtles and tortoises play important., albeit incompletely understood and largely unappreciated, roles in both the ecology of their ecosystem, and in the economy and sociology of the human cultures that interact with these enigmatic creatures, South-east Asia is home to a high diversity of freshwater turtle species. However, none of the species knows from Borneo have been studied at length and consequently, little is know of their ecology. The present work is the first ecological study of Amyda cartilaginea not only in Borneo, but Malaysia.
Igor G. Danilov - One of the best experts on this subject based on the ideXlab platform.
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cretaceous soft shelled turtles trionychidae of mongolia new diversity records and a revision
Journal of Systematic Palaeontology, 2014Co-Authors: Igor G. Danilov, Ren Hirayama, Vladimir B. Sukhanov, Shigeru Suzuki, Mahito Watabe, Natasha S. VitekAbstract:This paper is devoted to the description and revision of material of Cretaceous soft-shelled turtles (Trionychidae) of Mongolia. It includes the description of seven trionychid species, six of which are new, and two new genera: the cyclanorbine Nemegtemys conflata gen. et sp. nov. from the Nemegt Formation (Maastrichtian), and the trionychines Gobiapalone breviplastra gen. et sp. nov. from the Nemegt and Barungoyot (Campanian) formations, G. orlovi from the Baynshire Formation (Cenomanian–Santonian), ‘Trionyx’ baynshirensis sp. nov. from the Baynshire Formation, ‘T.’ gilbentuensis sp. nov. from the Nemegt Formation, ‘T.’ gobiensis sp. nov. from the Nemegt Formation, and ‘T.’ shiluutulensis sp. nov. from an unknown formation (Campanian). In addition, one shell from the ?Baynshire Formation of Khermin Tsav is assigned to Gobiapalone sp. The type material of Amyda menneri is considered to be Trionychidae indet. and Amyda menneri to be a nomen dubium. Finally, we revise other available materials of Cretaceous...
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Cretaceous soft-shelled turtles (Trionychidae) of Mongolia: new diversity, records and a revision
2014Co-Authors: Igor G. Danilov, Ren Hirayama, Vladimir B. Sukhanov, Shigeru Suzuki, Mahito Watabe, Natasha S. VitekAbstract:This paper is devoted to the description and revision of material of Cretaceous soft-shelled turtles (Trionychidae) of Mongolia. It includes the description of seven trionychid species, six of which are new, and two new genera: the cyclanorbine Nemegtemys conflata gen. et sp. nov. from the Nemegt Formation (Maastrichtian), and the trionychines Gobiapalone breviplastra gen. et sp. nov. from the Nemegt and Barungoyot (Campanian) formations, G. orlovi from the Baynshire Formation (Cenomanian–Santonian), ‘Trionyx’ baynshirensis sp. nov. from the Baynshire Formation, ‘T.’ gilbentuensis sp. nov. from the Nemegt Formation, ‘T.’ gobiensis sp. nov. from the Nemegt Formation, and ‘T.’ shiluutulensis sp. nov. from an unknown formation (Campanian). In addition, one shell from the ?Baynshire Formation of Khermin Tsav is assigned to Gobiapalone sp. The type material of Amyda menneri is considered to be Trionychidae indet. and Amyda menneri to be a nomen dubium. Finally, we revise other available materials of Cretaceous trionychids from 45 localities in Mongolia. Nemegtemys conflata, if correctly assigned, is the earliest known member of Cyclanorbinae. The two species of the new genus Gobiapalone are included in two phylogenetic analyses of Trionychidae. In both analyses Gobiapalone is monophyletic. In the first analysis, Gobiapalone is placed within Apalonina. In the second analysis, Gobiapalone is sister to Apalonina. Thus, the results of both analyses show that Apalonina, which is a rather advanced and well-supported trionychid clade, or its closest sister taxon (stem-Apalonina), were present in the Late Cretaceous of Asia. These results suggest that most other supra-generic clades of modern trionychids had been established in Asia by the Late Cretaceous. That suggestion is supported by the discovery of a cyclanorbine Nemegtemys conflata in the Late Cretaceous of Mongolia. Finally we summarize the latest data on temporal and geographical distributions of Cretaceous Trionychidae of Asia and North America.http://zoobank.org/urn:lsid:zoobank.org:pub:921DA1C5-C4B2-463D-A49D-608024C6036A
Indraneil Das - One of the best experts on this subject based on the ideXlab platform.
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Cultural Exploitation of Freshwater Turtles in Sarawak, Malaysian Borneo
Chelonian Conservation and Biology, 2008Co-Authors: Karen A. Jensen, Indraneil DasAbstract:Abstract We investigated the cultural exploitation of nonmarine turtles in Sarawak State, Malaysia. Turtles are primarily used for food, and the Asian softshell turtle, Amyda cartilaginea, appears to be the most desirable species. Other local demands include the pet trade, which involves both local and exotic species of turtles.
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Dietary Observations on the Asian Softshell Turtle (Amyda cartilaginea) from Sarawak, Malaysian Borneo
Chelonian Conservation and Biology, 2008Co-Authors: Karen A. Jensen, Indraneil DasAbstract:ABSTRACT We examined the diet of Amyda cartilaginea from 2 localities in Sarawak: Loagan Bunut National Park and Balai Ringin. The most commonly found items in stomach contents, when using percentage frequency of occurrence, were plant material (77%) and unknown vertebrate parts (55%). Fecal analysis indicated similar results: plant material (100%), unknown vertebrate parts (84%), fish (69%), and unknown arthropods (62%). Results indicate that A. cartilaginea is an opportunistic omnivore.
Akihiko Kondo - One of the best experts on this subject based on the ideXlab platform.
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Development of novel cell surface display in Corynebacterium glutamicum using porin.
Applied microbiology and biotechnology, 2009Co-Authors: Toshihiro Tateno, Hideki Fukuda, Tsutomu Tanaka, Kazuki Hatada, Akihiko KondoAbstract:We have developed a novel cell surface display in Corynebacterium glutamicum using porin proteins as anchor proteins. Porins are localized at C. glutamicum mycolic acid layer and exist as a hexamer. We used α-amylase from Streptococcus bovis 148 (AmyA) as a model protein to be displayed on the C. glutamicum cell surface. AmyA was fused to the C terminus of the porins PorB, PorC, or PorH. Expression vectors using fused proteins under the control of the cspB promoter were constructed and introduced into the C. glutamicum Cm strain. Immunostaining microscopy and flow cytometric analysis revealed that PorB-AmyA, PorC-AmyA, and PorH-AmyA were displayed on the C. glutamicum cell surface. AmyA activity was only detected in the cell fraction of C. glutamicum cells that displayed AmyA fused to PorB, PorC or PorH and AmyA activity was not detected in the supernatants of C. glutamicum culture broths after 72 h cultivation. Thus, we have demonstrated that C. glutamicum porins are very efficient anchor proteins for protein display in C. glutamicum.
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direct production of cadaverine from soluble starch using corynebacterium glutamicum coexpressing α amylase and lysine decarboxylase
Applied Microbiology and Biotechnology, 2009Co-Authors: Toshihiro Tateno, Hideki Fukuda, Yusuke Okada, Takeyuki Tsuchidate, Tsutomu Tanaka, Akihiko KondoAbstract:Here, we demonstrated the one-step production of cadaverine from starch using a Corynebacterium glutamicum strain coexpressing Streptococcus bovis 148 α-amylase (AmyA) and Escherichia coli K-12 lysine decarboxylase (CadA). We constructed the E. coli–C. glutamicum shuttle vector, which produces CadA under the control of the high constitutive expression (HCE) promoter, and transformed this vector into C. glutamicum CSS secreting AmyA. The engineered C. glutamicum expressed both CadA and AmyA, which retained their activity. We performed cadaverine fermentation using 50 g/l soluble starch as the sole carbon source without pyridoxal-5’-phosphate, which is the coenzyme for CadA. C. glutamicum coexpressing AmyA and CadA successfully produced cadaverine from soluble starch and the yield of cadaverine was 23.4 mM after 21 h. CadA expression levels under the control of the HCE promoter were assumed to be sufficient to convert l-lysine to cadaverine, as there was no accumulation of l-lysine in the culture medium during fermentation. Thus, we demonstrated that C. glutamicum has great potential to produce cadaverine from biomass resources.
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efficient production of optically pure d lactic acid from raw corn starch by using a genetically modified l lactate dehydrogenase gene deficient and α amylase secreting lactobacillus plantarum strain
Applied and Environmental Microbiology, 2009Co-Authors: Kenji Okano, Hideki Fukuda, Tsutomu Tanaka, Qiao Zhang, Satoru Shinkawa, Shogo Yoshida, Akihiko KondoAbstract:In order to achieve direct and efficient fermentation of optically pure d-lactic acid from raw corn starch, we constructed l-lactate dehydrogenase gene (ldhL1)-deficient Lactobacillus plantarum and introduced a plasmid encoding Streptococcus bovis 148 α-amylase (AmyA). The resulting strain produced only d-lactic acid from glucose and successfully expressed amyA. With the aid of secreting AmyA, direct d-lactic acid fermentation from raw corn starch was accomplished. After 48 h of fermentation, 73.2 g/liter of lactic acid was produced with a high yield (0.85 g per g of consumed sugar) and an optical purity of 99.6%. Moreover, a strain replacing the ldhL1 gene with an amyA-secreting expression cassette was constructed. Using this strain, direct d-lactic acid fermentation from raw corn starch was accomplished in the absence of selective pressure by antibiotics. This is the first report of direct d-lactic acid fermentation from raw starch.
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direct production of l lysine from raw corn starch by corynebacterium glutamicum secreting streptococcus bovis α amylase using cspb promoter and signal sequence
Applied Microbiology and Biotechnology, 2007Co-Authors: Toshihiro Tateno, Hideki Fukuda, Akihiko KondoAbstract:Corynebacterium glutamicum is an important microorganism in the industrial production of amino acids. We engineered a strain of C. glutamicum that secretes α-amylase from Streptococcus bovis 148 (AmyA) for the efficient utilization of raw starch. Among the promoters and signal sequences tested, those of cspB from C. glutamicum possessed the highest expression level. The fusion gene was introduced into the homoserine dehydrogenase gene locus on the chromosome by homologous recombination. L-Lysine fermentation was conducted using C. glutamicum secreting AmyA in the growth medium containing 50 g/l of raw corn starch as the sole carbon source at various temperatures in the range 30 to 40°C. Efficient L-lysine production and raw starch degradation were achieved at 34 and 37°C, respectively. The α-amylase activity using raw corn starch was more than 2.5 times higher than that using glucose as the sole carbon source during L-lysine fermentation. AmyA expression under the control of cspB promoter was assumed to be induced when raw starch was used as the sole carbon source. These results indicate that efficient simultaneous saccharification and fermentation of raw corn starch to L-lysine were achieved by C. glutamicum secreting AmyA using the cspB promoter and signal sequence.
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Display of active enzymes on the cell surface of Escherichia coli using PgsA anchor protein and their application to bioconversion
Applied Microbiology and Biotechnology, 2005Co-Authors: Junya Narita, Toshihiro Tateno, Tomomitsu Sewaki, Kenji Okano, Moon-hee Sung, Takanori Tanino, Hideki Fukuda, Akihiko KondoAbstract:We have developed a novel Escherichia coli cell surface display system by employing PgsA as an anchoring motif. In our display system, C-terminal fusion to PgsA anchor protein from Bacillus subtilis was used. The enzymes selected for display were α-amylase (AmyA) from Streptococcus bovis 148 and lipase B (CALB) from Candida antarctica. The molecular mass values of AmyA and CALB are approximately 77 and 34 kDa, respectively. The enzymes were displayed on the surface as a fusion protein with a FLAG peptide tag at the C terminus. Both the PgsA-AmyA-FLAG and PgsA-CALB-FLAG fusion proteins were shown to be displayed by immunofluorescence labeling using anti-FLAG antibody. The displayed enzymes were active forms, and AmyA and CALB activities reached 990 U/g (dry cell weight) and 4.6 U/g (dry cell weight), respectively. AmyA-displaying E. coli cells grew utilizing cornstarch as the sole carbon source, while CALB-displaying E. coli cells catalyzed enantioselective transesterification, indicating that they are effective whole-cell biocatalysts. Since a target enzyme with a size of 77 kDa and an industrially useful lipase have been successfully displayed on the cell surface of E. coli for the first time, PgsA protein is probably a useful anchoring motif to display various enzymes.
