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101.
Carlos Soccol José Rodríguez León Bernard Marin Sevastianos Roussos Maurice Raimbault 《Biotechnology Techniques》1993,7(8):563-568
Summary Growth kinetics of Rhizopus arrhizus MUCL 28168 were determined for different treatments of cassava during solid state fermentation. The best case gave a specific growth rate () of 0.24 h-1, a yield calculated on a basis that oxygen consumption (Yx/o) was 2.9 g biomass. g-1 O2 consumed and the maintenance coefficient (m) was 0.004 g O2 consumed. g-1 biomass. h-1. 相似文献
102.
Male zebra finches normally learn their song from adult models during a restricted period of juvenile development. If song models are not available then, juveniles develop an isolate song which can be modified in adulthood. In this report we investigate the features of juvenile experience that underly the timing of song learning. Juvenile males raised in soundproof chambers or in visual isolation from conspecifics developed stable isolate song. However, whereas visual isolate song notes were similar to those of colony-reared males, soundproof chamber isolates included many phonologically abnormal notes in their songs. Despite having stable isolate songs, both groups copied new notes from tutors presented to them in adulthood (2.7 notes per bird for soundproof chamber isolates, 4.4 notes per bird for visual isolates). Old notes were often modified or eliminated. We infer that social interactions with live tutors are normally important for closing the sensitive period for song learning. Lesions of a forebrain nucleus (IMAN) had previously been shown to disrupt juvenile song learning, but not maintenance of adult song for up to 5 weeks after surgery. In this study, colony-reared adult males given bilateral lesions of IMAN retained all their song notes for up to 4–7.5 months after lesioning. However, similar lesions blocked all song note acquisition in adulthood by both visual and soundproof chamber isolates. Other work has shown that intact hearing is necessary for the maintenance of adult zebra finch song. We infer that auditory pathways used for song maintenance and acquisition differ: IMAN is necessary for auditorily guided song acquisition—whether by juveniles or adults—but not for adult auditorily guided song maintenance. © 1993 John Wiley & Sons, Inc. 相似文献
103.
Coelho-Rocha Nina Dias de Jesus Luís Cláudio Lima Barroso Fernanda Alvarenga Lima da Silva Tales Fernando Ferreira Enio Gonçalves José Eduardo dos Santos Martins Flaviano de Oliveira Carvalho Rodrigo Dias Barh Debmalya Azevedo Vasco Ariston de Carvalho 《Probiotics and antimicrobial proteins》2023,15(1):160-174
Probiotics and Antimicrobial Proteins - Beneficial effects of Lactiplantibacillus plantarum strains have been widely reported. Knowing that the effects of probiotic bacteria are strain-dependent,... 相似文献
104.
Roberto de la Herrán Miguel Hermida Juan Andres Rubiolo Jèssica Gómez-Garrido Fernando Cruz Francisca Robles Rafael Navajas-Pérez Andres Blanco Paula Rodriguez Villamayor Dorinda Torres Pablo Sánchez-Quinteiro Daniel Ramirez Maria Esther Rodríguez Alberto Arias-Pérez Ismael Cross Neil Duncan Teresa Martínez-Peña Ana Riaza Adrian Millán M. Cristina De Rosa Davide Pirolli Marta Gut Carmen Bouza Diego Robledo Laureana Rebordinos Tyler Alioto Carmelo Ruíz-Rejón Paulino Martínez 《Molecular ecology resources》2023,23(4):886-904
Sex determination (SD) shows huge variation among fish and a high evolutionary rate, as illustrated by the Pleuronectiformes (flatfishes). This order is characterized by its adaptation to demersal life, compact genomes and diversity of SD mechanisms. Here, we assembled the Solea senegalensis genome, a flatfish of great commercial value, into 82 contigs (614 Mb) combining long- and short-read sequencing, which were next scaffolded using a highly dense genetic map (28,838 markers, 21 linkage groups), representing 98.9% of the assembly. Further, we established the correspondence between the assembly and the 21 chromosomes by using BAC-FISH. Whole genome resequencing of six males and six females enabled the identification of 41 single nucleotide polymorphism variants in the follicle stimulating hormone receptor (fshr) consistent with an XX/XY SD system. The observed sex association was validated in a broader independent sample, providing a novel molecular sexing tool. The fshr gene displayed differential expression between male and female gonads from 86 days post-fertilization, when the gonad is still an undifferentiated primordium, concomitant with the activation of amh and cyp19a1a, testis and ovary marker genes, respectively, in males and females. The Y-linked fshr allele, which included 24 nonsynonymous variants and showed a highly divergent 3D protein structure, was overexpressed in males compared to the X-linked allele at all stages of gonadal differentiation. We hypothesize a mechanism hampering the action of the follicle stimulating hormone driving the undifferentiated gonad toward testis. 相似文献
105.
106.
M. Berrocal S. Huerta J. Rodríguez M. Pérez-Leblic M. E. Arias 《World journal of microbiology & biotechnology》1996,12(1):101-102
In surface cultures of Streptomyces cyaneus var. viridochromogenes, NaCl depressed water activity (a
w) without supporting growth. Reducing a
w from 0.987 to 0.951 led to 3- and 4-fold increases in intracellular and extracellular phenol oxidase activities, respectively. 相似文献
107.
Maria J. P. van Dongen Sybren S. Wijmenga Ramón Eritja Fernando Azorín Cornelis W. Hilbers 《Journal of biomolecular NMR》1996,8(2):207-212
Summary A new application of the HMBC experiment is presented that provides a useful means to discriminate between H2 and H8 proton resonances, to assign the base proton resonances to the various residue types and, most importantly, to correlate the H2 and H8 protons for adenine or inosine residues in natural abundance 13C fragments. The utility of this experiment is demonstrated for an unlabeled DNA 20-mer. Thanks to the obtained results, preliminary conclusions could be drawn regarding the molecular conformations of the non-canonical G/I-A base pairs in the hairpin formed by this fragment. 相似文献
108.
Vittorio Moretto Fernando Formaggio Marco Crisma Gian Maria Bonora Claudio Toniolo Ettore Benedetti Antonello Santini Michele Saviano Benedetto Di Blasio Carlo Pedone 《Journal of peptide science》1996,2(1):14-27
A complete series of terminally blocked, monodispersed homo-oligopeptides (to the pentamer level) from the sterically demanding, medium-ring alicyclic Cα,α-disubstituted glycine 1-aminocyclooctane-1-carb oxylic acid (Ac8c), and two Ala/Ac8c tripeptides, were synthesized by solution methods and fully characterized. The preferred conformation of all the oligopeptides was determined in deuterochloroform solution by IR absorption and 1H-NMR. The molecular structures of the amino acid derivative Z-Ac8c-OH, the dipeptide pBrBz- (Ac8c)2-OH and the tripeptide pBrBz-(Ac8c)3-OtBu were assessed in the crystal state by X-ray diffraction. Conformational energy computations were performed on the monopeptide Ac-Ac8c-NHMe. Taken together, the results obtained strongly support the view that the Ac8c residue is an effective β-turn and helix former. A comparison is also made with the conformational preferences of α-aminoisobutyric acid, the prototype of Cα, α-disubstituted glycines, and of the other members of the family of 1-aminocycloalkane-1-carboxylic acids (Acnc, with n=3, 5–7) investigated so far. The implications for the use of the Ac8c residue in peptide conformational design are considered. 相似文献
109.
J. C. Rodríguez-Aguilera F. Navarro A. Arroyo F. J. Alcaín J. M. Villalba P. Navas 《Protoplasma》1995,184(1-4):229-232
Summary Ascorbate is stabilized in the presence of HL-60 cells. Our results showed that cAMP derivatives and agents that increase cAMP stimulate the ability of HL-60 cells to stabilize ascorbate. On the other hand, tunicamycin, a glycosilation-interfering agent, inhibited this ability. The ascorbate stabilization in the presence of HL-60 cells has been questioned as a simple chemical effect. Further properties and controls about the enzymatic nature of this stabilization are described and discussed. This data, together with hormonal regulation, support the hypothesis that an enzymatic redox system located at the plasma membrane is responsible of the extracellular ascorbate stabilization by HL-60 cells.Abbreviations AFR
ascorbate free radicals
- FCS
fetal calf serum
- Sp-cAMPS
Sp-cyclic adenosine monophosphothionate
- Rp-cAMPS
Rp-cyclic adenosine monophosphothionate 相似文献
110.
Fusarium oxysporum f. sp. vasinfectum penetration hyphae infect living cells in the meristematic zone of cotton (Gossypium barbadense L.) roots. We characterized wall modifications induced by the fungus during infection of the protodermis using antibodies against callose, arabinogalactan-proteins, xyloglucan, pectin, polygalacturonic acid and rhamnogalacturonan I in high-pressure frozen, freeze-substituted root tissue. Using quantitative immunogold labelling we compared the cell walls before and after hyphal contact, cell plates with plasmodesmata during cytokinesis, and wall appositions induced by fungal contact. In the already-existing wall, fungal contact induced only minor modifications such as an increase of xyloglucan epitopes. Wall appositions mostly exhibited epitopes similar to the cell plate except that wall appositions had a much higher callose content. This study shows that wall appositions induced by Fusarium oxysporum hyphae are the result of normal cell wall synthesis and the addition of large amounts of callose. The appositions do not stop fungal growth. 相似文献