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961.
Jhoanne Hansen Albert Garreta Maria Benincasa M. Carmen Fusté Montserrat Busquets Angeles Manresa 《Applied microbiology and biotechnology》2013,97(11):4737-4747
Lipoxygenases (EC. 1.13.11.12) are a non-heme iron enzymes consisting of one polypeptide chain folded into two domains, the N-terminal domain and the catalytic moiety β-barrel domain. They catalyze the dioxygenation of 1Z,4Z-pentadiene moieties of polyunsaturated fatty acids obtaining hydroperoxy fatty acids. For years, the presence of lipoxygenases was considered a eukaryotic feature, present in mammals, plants, small marine invertebrates, and fungi, but now, some lipoxygenase sequences have been detected on prokaryotic organisms, changing the idea that lipoxygenases are exclusively a eukaryotic affair. Lipoxygenases are involved in different types of reactions on eukaryote organisms where the biological role and the structural characteristics of these enzymes are well studied. However, these aspects of the bacterial lipoxygenases have not yet been elucidated and are unknown. This revision discusses biochemical aspects, biological applications, and some characteristics of these enzymes and tries to determine the existence of a subfamily of bacterial lipoxygenases in the context of the phylogeny of prokaryotic lipoxygenases, supporting the results of phylogenetic analyzes with the comparison and discussion of structural information of the first prokaryotic lipoxygenase crystallized and other eukaryotic lipoxygenases structures. 相似文献
962.
963.
Ornithine cyclodeaminase activity in Rhizobium meliloti 总被引:1,自引:0,他引:1
María José Soto Pieter van Dillewijn José Olivares Nicolás Toro 《FEMS microbiology letters》1994,119(1-2):209-213
Abstract Deamination of L-ornithine to L-proline by ornithine cyclodeaminase is an unusual enzyme reaction that has been shown to occur in only a few bacteria. Rhizobium meliloti strains GR4, 2011 and 41 are able to use ornithine as the sole carbon and nitrogen source. The main pathway of ornithine utilization in strain GR4 depends on ornithine cyclodeaminase activity. In addition, this enzymatic activity has been found to be dependent on NAD+ and L-arginine similar to Agrobacterium ornithine cyclodeaminases. The ornithine cyclodeaminase activity is also expressed in R. meliloti strains 2011 and 41 growing with L-ornithine. 相似文献
964.
Maria Pernas Victor Sanchez-Merino Concepcion Casado Alberto Merino-Mansilla Isabel Olivares Eloisa Yuste Cecilio Lopez-Galindez 《PloS one》2015,10(8)
This study evaluated the neutralization breadth in dually infected (DI) HIV-1 long-term non-progressor elite controller patients (LTNP-EC) using a representative minipanel of 6 viruses from 5 different subtypes. Our results showed an improved neutralization breadth in DI LTNP-EC patients when compared with matched LTNP single-infected patients. The role of viral diversity in neutralization was estimated with the Shannon Entropy and the p-distance in viral quasispecies. We found a positive correlation between neutralization breadth and diversity within the viral quasispecies. This correlation could explain why a group of LTNP-EC patients developed a broad neutralizing response despite having undetectable levels of viremia. 相似文献
965.
Daniel Zizumbo-Villarreal Fernando González-Zozaya Angeles Olay-Barrientos Rafael Platas-Ruíz Mariza Cuevas-Sagardí Laura Almendros-López Patricia Colunga-GarcíaMarín 《Economic botany》2009,63(3):288-302
Archaeological Evidence of the Cultural Importance of
Agave spp
. in Pre-Hispanic Colima, Mexico. Production of agave-based food and fermented alcoholic beverages was highly relevant culturally and socially in pre-European
contact western Mesoamerica. It has been hypothesized that agave distillation in western Mexico began in Colima in the early
Colonial Era through adaptation of introduced Filipino techniques. Archaeological evidence is presented confirming the cultural
and social significance of agave in Colima before contact, one of the fundamental conditions supporting this hypothesis. An
analysis of circular subterranean stone structures in residential and ceremonial contexts (Classic and Postclassic periods:
200–1500 common era [CE]), and a comparison with stone ovens currently used to cook agave for the creation of spirits, indicate
these structures were probably used for preparing food, including agave. Analysis of funerary ceramic vessel offerings with
agave images (Colima phase: 400–600 CE) are reported for the first time. Their characteristics, and those of the associated
burials and tombs, suggest those buried were agave growers or alcoholic beverage producers who fulfilled relevant roles in
the society. Most of the agave images probably represent Agave angustifolia Lem and its cultivation. During the Colonial Era, the cultural and social relevance of agaves almost disappeared in Colima,
possibly due to drastic reductions in the native human population, changing land use practices, and prohibitions against the
production and sale of native alcoholic beverages. 相似文献
966.
967.
Manuel Nieves-Cordones Alberto Lara Martha Silva Jesús Amo Pascual Rodriguez-Sepulveda Rosa M. Rivero Vicente Martínez M. Angeles Botella Francisco Rubio 《Plant, cell & environment》2020,43(7):1707-1721
Root K+ acquisition is a key process for plant growth and development, extensively studied in the model plant Arabidopsis thaliana. Because important differences may exist among species, translational research supported by specific studies is needed in crops such as tomato. Here we present a reverse genetics study to demonstrate the role of the SlHAK5 K+ transporter in tomato K+ nutrition, Cs+ accumulation and its fertility. slhak5 KO lines, generated by CRISPR-Cas edition, were characterized in growth experiments, Rb+ and Cs+ uptake tests and root cells K+-induced plasma membrane depolarizations. Pollen viability and its K+ accumulation capacity were estimated by using the K+-sensitive dye Ion Potassium Green 4. SlHAK5 is the major system for high-affinity root K+ uptake required for plant growth at low K+, even in the presence of salinity. It also constitutes a pathway for Cs+ entry in tomato plants with a strong impact on fruit Cs+ accumulation. SlHAK5 also contributes to pollen K+ uptake and viability and its absence produces almost seedless fruits. Knowledge gained into SlHAK5 can serve as a model for other crops with fleshy fruits and it can help to generate tools to develop low Cs+ or seedless fruits crops. 相似文献
968.
Cristina Cid Laura Garcia‐Descalzo Victor Casado‐Lafuente Ricardo Amils Angeles Aguilera 《Proteomics》2010,10(10):2026-2036
A proteomic approach including 2‐DE and MALDI‐TOF analysis has been developed to identify the soluble proteins of the unicellular photosynthetic algae Chlamydomonas sp. isolated from an extreme acidic environment, Río Tinto (southwest Spain). We have analyzed the soluble proteome obtained from whole cells growing on metal‐rich natural acidic water from the river in comparison with the same strain growing in artificial BG‐11 media. The most drastic effect was the decrease in the abundance of the ribulose‐1,5‐biphosphate carboxylase as well as other enzymes related to photosynthesis. However, phytochrome B, phosphoribulokinase, and phosphoglycerate kinase were upregulated when cells were grown in metal‐rich acidic water. Besides, increased accumulation of two Hsps, Hsp70 and Hsp90 as well as other stress‐related enzymes were also found in the cells growing in natural acidic water. These results suggest that naturally occurring metal‐rich water induces a stress response in acidophilic Chlamydomonas forcing algal cells to reorganize their metabolic pathways as an adaptive response to these environmental conditions. 相似文献
969.
María J. Soto Ana Domínguez-Ferreras Daniel Pérez-Mendoza Juan Sanjuán José Olivares 《Cellular microbiology》2009,11(3):381-388
Pathogenic bacteria and mutualistic rhizobia are able to invade and establish chronic infections within their host plants. The success of these plant–bacteria interactions requires evasion of the plant innate immunity by either avoiding recognition or by suppressing host defences. The primary plant innate immunity is triggered upon recognition of common microbe-associated molecular patterns. Different studies reveal striking similarities between the molecular bases underlying the perception of rhizobial nodulation factors and microbe-associated molecular patterns from plant pathogens. However, in contrast to general elicitors, nodulation factors can control plant defences when recognized by their cognate legumes. Nevertheless, in response to rhizobial infection, legumes show transient or local defence-like responses suggesting that Rhizobium is perceived as an intruder although the plant immunity is controlled. Whether these responses are involved in limiting the number of infections or whether they are required for the progression of the interaction is not yet clear. Further similarities in both plant–pathogen and Rhizobium –legume associations are factors such as surface polysaccharides, quorum sensing signals and secreted proteins, which play important roles in modulating plant defence responses and determining the outcome of the interactions. 相似文献
970.
Esther León Carlos González Montserrat Elías-Arnanz S. Padmanabhan M. Angeles Jiménez 《Biomolecular NMR assignments》2009,3(1):37-40
The CarS antirepressor activates a photo-inducible promoter in Myxococcus xanthus by physically interacting with the CarA repressor and eliminating the latter’s binding to operator DNA. Interestingly, interactions
with both CarS and operator are crucially dependent on the DNA recognition helix of the CarA winged-helix DNA-binding domain.
The CarA–CarS and the CarA-operator interfaces therefore overlap, and CarS may have structural features that mimic operator
DNA. CarS has no known sequence homologues and its Gly and Pro contents are unusually high. Here, we report 1H, 13C and 15N backbone and side chain assignments of CarS1, an 86-residue truncated yet fully functional variant of CarS. Secondary structural
elements inferred from these data differ from those predicted from sequence. 相似文献