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991.
Thomas Eichert José Javier Peguero-Pina Eustaquio Gil-Pelegrín Antonio Heredia Victoria Fernández 《Physiologia plantarum》2010,138(1):48-59
There is increasing evidence suggesting that iron (Fe) deficiency induces not only leaf chlorosis and a decline of photosynthesis, but also structural changes in leaf morphology, which might affect the functionality of leaves. In this study, we investigated the effects of Fe deficiency on the water relations of peach ( Prunus persica (L.) Batsch.) leaves and the responses of previously chlorotic leaves to Fe resupply via the root or the leaf. Iron deficiency induced a decline of maximum potential photosystem II (PSII) efficiency (F V /F M ), of rates of net photosynthesis and transpiration and of water use efficiency. Iron chlorosis was associated with a reduction of leaf xylem vessel size and of leaf hydraulic conductance. In the course of the day, water potentials in chlorotic leaves remained higher (less negative) than in green leaves. In chlorotic leaves, normal stomatal functioning was disturbed, as evidenced by the lack of opening upon withdrawal of external CO2 and stomatal closure after sudden illumination of previously darkened leaves. We conclude that the Fe deficiency induced limitations of xylem conductivity elicited a water saving strategy, which poses an additional challenge to plant growth on high pH, calcareous soils. Fertilisation with Fe improved photosynthetic performance but the proper xylem structure and water relations of leaves were not fully restored, indicating that Fe must be available at the first stages of leaf growth and development. 相似文献
992.
Joana Tomomi Sumikawa Marlon Vilela de Brito Maria Ligia Rodrigues Macedo Adriana F. Uchoa Antonio Miranda Ana Paula U. Araujo Rosemeire A. Silva-Lucca Misako Uemura Sampaio Maria Luiza Vilela Oliva 《Phytochemistry》2010,71(2-3):214-220
Three plant proteinase inhibitors BbKI (kallikrein inhibitor) and BbCI (cruzipain inhibitor) from Bauhinia bauhinioides, and a BrTI (trypsin inhibitor) from B. rufa, were examined for other effects in Callosobruchus maculatus development; of these only BrTI affected bruchid emergence. BrTI and BbKI share 81% identities in their primary sequences and the major differences between them are the regions comprising the RGD and RGE motifs in BrTI. These sequences were shown to be essential for BrTI insecticidal activity, since a modified BbKI [that is a recombinant form (BbKIm) with some amino acid residues replaced by those found in BrTI sequence] also strongly inhibited insect development. By using synthetic peptides related to the BrTI sequence, YLEAPVARGDGGLA-NH2 (RGE) and IVYYPDRGETGL-NH2 (RGE), it was found that the peptide with an RGE sequence was able to block normal development of C. maculatus larvae (ED50 0.16% and LD50 0.09%), this being even more effective than the native protein. 相似文献
993.
994.
Javier Tamames Juan José Abellán Miguel Pignatelli Antonio Camacho Andrés Moya 《BMC microbiology》2010,10(1):85
Background
The increasing availability of gene sequences of prokaryotic species in samples extracted from all kind of locations allows addressing the study of the influence of environmental patterns in prokaryotic biodiversity. We present a comprehensive study to address the potential existence of environmental preferences of prokaryotic taxa and the commonness of the specialist and generalist strategies. We also assessed the most significant environmental factors shaping the environmental distribution of taxa. 相似文献995.
Eva García-Ruiz Diana Maté Antonio Ballesteros Angel T Martinez Miguel Alcalde 《Microbial cell factories》2010,9(1):17
Background
In the picture of a laboratory evolution experiment, to improve the thermostability whilst maintaining the activity requires of suitable procedures to generate diversity in combination with robust high-throughput protocols. The current work describes how to achieve this goal by engineering ligninolytic oxidoreductases (a high-redox potential laccase -HRPL- and a versatile peroxidase, -VP-) functionally expressed in Saccharomyces cerevisiae. 相似文献996.
Like natural viruses, manmade protein cages for drug delivery are to be ideally formed by repetitive subunits with self-assembling
properties, mimicking viral functions and molecular organization. Naturally formed nanostructures (such as viruses, flagella
or simpler protein oligomers) can be engineered to acquire specific traits of interest in biomedicine, for instance through
the addition of cell targeting agents for desired biodistribution and specific delivery of associated drugs. However, fully
artificial constructs would be highly desirable regarding finest tuning and adaptation to precise therapeutic purposes. Although
engineering of protein assembling is still in its infancy, arising principles and promising strategies of protein manipulation
point out the rational construction of nanoscale protein cages as a feasible concept, reachable through conventional recombinant
DNA technologies and microbial protein production. 相似文献
997.
Luis Gracia Elena Ibarz Sergio Puértolas José Cegoñino Fernando López-Prats Juan J Panisello Antonio Herrera 《Biomedical engineering online》2010,9(1):22
Background
A hip replacement with a cemented or cementless femoral stem produces an effect on the bone called adaptive remodelling, attributable to mechanical and biological factors. All of the cementless prostheses designs try to achieve an optimal load transfer in order to avoid stress-shielding, which produces an osteopenia. 相似文献998.
Sergio Puértolas José M Pérez-García Luis Gracia José Cegoñino Elena Ibarz José A Puértolas Antonio Herrera 《Biomedical engineering online》2010,9(1):49
Background
The proximal interphalange joint (PIP) is fundamental for the functional nature of the hand. The contracture in flexion of the PIP, secondary to traumatisms or illnesses leads to an important functional loss. The use of correcting splints is the common procedure for treating this problem. Its functioning is based on the application of a small load and a prolonged stress which can be dynamic, static progressive or static serial. 相似文献999.
Lucia Peluso Cristiana de Luca Silvia Bozza Antonio Leonardi Gloria Giovannini Alfonso Lavorgna Gaetano De Rosa Massimo Mascolo Loredana Ortega De Luna Maria Rosaria Catania Luigina Romani Fabio Rossano 《BMC microbiology》2010,10(1):1-11
Background
Porcine reproductive and respiratory syndrome (PRRS) has now been widely recognized as an economically important disease. The objective of this study was to compare the molecular and biological characteristics of porcine reproductive and respiratory syndrome virus (PRRSV) field isolates in China to those of the modified live virus (MLV) PRRS vaccine and its parent strain (ATCC VR2332).Results
Five genes (GP2, GP3, GP4, GP5 and NSP2) of seven isolates of PRRSV from China, designated LS-4, HM-1, HQ-5, HQ-6, GC-2, GCH-3 and ST-7/2008, were sequenced and analyzed. Phylogenetic analyses based on the nucleotide sequence of the ORF2-5 and NSP2 showed that the seven Chinese isolates belonged to the same genetic subgroup and were related to the North American PRRSV genotype. Comparative analysis with the relevant sequences of another Chinese isolate (BJ-4) and North American (VR2332 and MLV) viruses revealed that these isolates have 80.8-92.9% homology with VR-2332, and 81.3-98.8% identity with MLV and 80.7-92.9% with BJ-4. All Nsp2 nonstructural protein of these seven isolates exhibited variations (a 29 amino acids deletion) in comparison with other North American PRRSV isolates. Therefore, these isolates were novel strain with unique amino acid composition. However, they all share more than 97% identity with other highly pathogenic Chinese PRRSV strains. Additionally, there are extensive amino acid (aa) mutations in the GP5 protein and the Nsp2 protein when compared with the previous isolates.Conclusions
These results might be useful to study the genetic diversity of PRRSV in China and to track the infection sources as well as for vaccines development. 相似文献1000.
Jennifer MP Woo Zhuofeng Lin Mohamad Navab Casey Van Dyck Yvette Trejo-Lopez Krystal MT Woo Hongyun Li Lawrence W Castellani Xuping Wang Noriko Iikuni Ornella J Rullo Hui Wu Antonio La Cava Alan M Fogelman Aldons J Lusis Betty P Tsao 《Arthritis research & therapy》2010,12(3):R93