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831.
Diogo Robl Priscila da Silva Delabona Patrícia dos Santos Costa Deise Juliana da Silva Lima Sarita Candida Rabelo Ida Chapaval Pimentel 《Biocatalysis and Biotransformation》2015,33(3):175-187
Fungal xylanases have been widely studied and various production methods have been proposed using submerged and solid-state fermentation. This class of enzyme is used to supplement cellulolytic enzyme cocktails in order to enhance the enzymatic hydrolysis of plant cell walls. The present work investigates the production of xylanase and other accessory enzymes by a recently isolated endophytic Aspergillus niger DR02 strain, using the pentose-rich liquor from hydrothermal pretreatment of sugarcane bagasse as carbon source. Batch and fed-batch submerged cultivation approaches were developed in order to minimize the toxicity of the liquor and increase enzyme production. Maximum xylanase activities obtained were 458.1 U/mL for constant fed-batch, 428.1 U/mL for exponential fed-batch, and 264.37 U/mL for pulsed fed-batch modes. The results indicated that carbon-limited fed-batch cultivation can reduce fungal catabolite repression, as well as overcome possible negative effects of toxic compounds present in the pentose-rich liquor. Enzymatic panel and mass spectrometric analyses of the fed-batch A. niger secretome showed high levels of xylanolytic enzymes (GH10, GH11, and GH62 Cazy families), together with cellobiohydrolase (G6 and GH7), β-glucosidase, β-xylosidase (GH3), and feruloyl esterase (CE1) accessory enzyme activities. The yields of glucose and xylose from enzymatic hydrolysis of hydrothermally pretreated sugarcane bagasse increased by 43.7 and 65.3%, respectively, when a commercial cellulase preparation was supplemented with the A. niger DR02 constant fed-batch enzyme complex. 相似文献
832.
833.
Terézia Horváthová Andrzej Antol Marcin Czarnoleski Paulina Kramarz Ulf Bauchinger Anna Maria Labecka Jan Koz?owski 《ZooKeys》2015,(515):67-79
According to the temperature-size rule (TSR), ectotherms developing under cold conditions experience slower growth as juveniles but reach a larger size at maturity. Whether temperature alone causes this phenomenon is unknown, but oxygen limitation can play a role in the temperature-size relationship. Oxygen may become limited under warm conditions when the resulting higher metabolism creates a greater demand for oxygen, especially in larger individuals. We examined the independent effects of oxygen concentration (10% and 22% O2) and temperature (15 °C and 22 °C) on duration of ontogenic development, which takes place within the maternal brood pouch (marsupium), and juvenile growth in the terrestrial isopod common rough woodlouse (Porcellio
scaber). Individuals inside the marsupium undergo the change from the aqueous to the gaseous environment. Under hypoxia, woodlice hatched from the marsupium sooner, but their subsequent growth was not affected by the level of oxygen. Marsupial development and juvenile growth were almost three times slower at low temperature, and marsupial development was longer in larger females but only in the cold treatment. These results show that temperature and oxygen are important ecological factors affecting developmental time and that the strength of the effect likely depends on the availability of oxygen in the environment. 相似文献
834.
Eduardo Fernando dos Santos Yuri Campanholo Grandinete Fernando Barbosa Noll 《ZooKeys》2015,(519):33-48
The first checklist of the Peruvian Hymenoptera listed 1169 species and subspecies of aculeate wasps, including 173 species of Pompilidae, seven of Scoliidae, 39 of Sphecidae and 403 of Vespidae. Herein are reported 32 species as new for Peru based mainly on the collection of the Natural History Museum, London. The loss of the endemic status of two species is also reported: Entypus
peruvianus (Rohwer) (Pompilidae: Pepsinae) and Omicron
ruficolle
schunkei Giordani Soika (Vespidae: Eumeninae). 相似文献
835.
Sinara Santos Jardim André Passaglia Schuch Camila Moura Pereira Elgion Lucio Silva Loreto 《Cell stress & chaperones》2015,20(5):843-851
There are many complex interactions between transposable elements (TEs) and host genomes. Environmental changes that induce stressful conditions help to contribute for increasing complexity of these interactions. The transposon mariner-Mos1 increases its mobilization under mild heat stress. It has putative heat shock elements (HSEs), which are probably activated by heat shock factors (HSFs). Ultraviolet radiation (UVC) is a stressor that has been suggested as able to activate heat shock protein genes (Hsp). In this study, we test the hypothesis that if UVC induces Hsp expression, as heat does, it could also promote mariner-Mos1 transposition and mobilization. The Drosophila simulans white-peach is a mutant lineage that indicates the mariner-Mos1 transposition phenotypically through the formation of mosaic eyes. This lineage was exposed to UVC or mild heat stress (28 °C) in order to evaluate the induction of mariner-Mos1 expression by RT-qPCR, as well as the mariner-Mos1 mobilization activity based on the count number of red spots in the eyes. The effects of both treatments on the developmental time of flies and cell cycle progression were also investigated. Both the analysis of eyes and mariner-Mos1 gene expression indicate that UVC radiation has no effect in mariner-Mos1 transposition, although heat increases the expression and mobilization of this TE soon after the treatment. However, the expression of Hsp70 gene increased after 24 h of UVC exposure, suggesting different pathway of activation. These results showed that heat promotes mariner-Mos1 mobilization, although UVC does not induce the expression or mobilization of this TE.
Electronic supplementary material
The online version of this article (doi:10.1007/s12192-015-0611-2) contains supplementary material, which is available to authorized users. 相似文献836.
Luís Eduardo Fernandes Rodrigues da Conceição Margarete Alice Fontes Saraiva Raphael Hermano Santos Diniz Juliana Oliveira Gustavo Dimas Barbosa Florencia Alvarez Lygia Fátima da Mata Correa Hygor Mezadri Mauricio Xavier Coutrim Robson José de Cássia Franco Afonso Candida Lucas Ieso Miranda Castro Rogelio Lopes Brandão 《Journal of industrial microbiology & biotechnology》2015,42(2):237-246
837.
Gatts Pedro Franco Marcos dos Santos Luciano Rocha Diogo de Sá Fabrício Netto Eurico Machado Phillipe Masi Bruno Zalmon Ilana 《Aquatic Ecology》2015,49(3):343-355
Aquatic Ecology - To investigate how variations in the small-scale distance between patchy reef modules affect the structure and composition of the associated ichthyofauna, concrete reefballs were... 相似文献
838.
839.
Phenotypic plasticity is a hallmark of the caste systems of social insects, expressed in their life history and morphological traits. These are best studied in bees. In their co-evolution with angiosperm plants, the females of corbiculate bees have acquired a specialized structure on their hind legs for collecting pollen. In the highly eusocial bees (Apini and Meliponini), this structure is however only present in workers and absent in queens. By means of histological sections and cell proliferation analysis we followed the developmental dynamics of the hind legs of queens and workers in the fourth and fifth larval instars. In parallel, we generated subtractive cDNA libraries for hind leg discs of queen and worker larvae by means of a Representational Difference Analysis (RDA). From the total of 135 unique sequences we selected 19 for RT-qPCR analysis, where six of these were confirmed as differing significantly in their expression between the two castes in the larval spinning stage. The development of complex structures such as the bees’ hind legs, requires diverse patterning mechanisms and signaling modules, as indicated by the set of differentially expressed genes related with cell adhesion and signaling pathways. 相似文献
840.
David E Loyola Cristell Navarro Paulina Uribe Katherine García Claudia Mella Diego Díaz Natalia Valdes Jaime Martínez-Urtaza Romilio T Espejo 《BMC genomics》2015,16(1)