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1.
Mewa Singh Tephillah Jeyaraj U. Prashanth Werner Kaumanns 《International journal of primatology》2011,32(1):167-176
Socioecology suggests that female distribution in space is determined by the distribution of food resources and the male distribution
is influenced by female distribution. Though studies have traditionally focused on females, males have received increasing
attention in recent years. We compared male–male relationships in lion-tailed macaques and bonnet macaques. Because bonnet
macaques have a high adult male:female sex ratio and are seasonal breeders whereas lion-tailed macaques have a low adult male:female
sex ratio and are largely aseasonal breeders, we predicted that bonnet macaque males would be spatially and socially more
tolerant of each other and would have less linear dominance relationships than lion-tailed macaques. We recorded male–male
and male–female relationships in 1 group of wild macaques of each species via scan sampling and 1–0 sampling. The results
revealed that lion-tailed macaque males largely remained at a distance from each other whereas bonnet macaque males remained
in close proximity to one another. Lion-tailed macaque males were more agonistic toward each other whereas bonnet macaque
males showed more affiliative interactions. The dominance hierarchy among lion-tailed macaque males was more linear than among
bonnet macaque males. Our data support the hypothesis that the study of spatial structuring, temporality of interactions,
and linearity of social relationships may contribute to a better understanding of macaque social systems. 相似文献
2.
Chin-Hong Ng Soon-Leong Lee Kevin Kit-Siong Ng Norwati Muhammad Wickneswari Ratnam 《Journal of genetics》2009,88(1):25-31
The mating system and seed variation of Acacia hybrid (A. mangium × A. auriculiformis) were studied using allozymes and random amplified polymorphic DNA (RAPD) markers, respectively. Multi-locus outcrossing
rate estimations indicated that the hybrid was predominantly outcrossed (mean±s.e. t
m = 0.86±0.01). Seed variation was investigated using 35 polymorphic RAPD fragments. An analysis of molecular variance (AMOVA)
revealed the highest genetic variation among seeds within a pod (66%–70%), followed by among pods within inflorescence (29%–37%),
and the least variation among inflorescences within tree (<1%). In addition, two to four RAPD profiles could be detected among
seeds within pod. Therefore, the results suggest that a maximum of four seeds per pod could be sampled for the establishment
of a mapping population for further studies. 相似文献
3.
Background
The presence of β-lactamases in Y. enterocolitica has been reported to vary with serovars, biovars and geographical origin of the isolates. An understanding of the β-lactamases in other related species is important for an overall perception of antibiotic resistance in yersiniae. The objective of this work was to study the characteristics of β-lactamases and their genes in strains of Y. intermedia and Y. frederiksenii, isolated from clinical and non-clinical sources in India. 相似文献4.
Erwinia carotovora subspecies betavasculorum, also known as E. betavasculorum and Pectobacterium betavasculorum, is a soil bacterium that has the capacity to cause root rot necrosis of sugarbeets. The qualitatively different pathogenicity exhibited by the virulent E. carotovora strain and two avirulent strains, a Citrobacter sp. and an Enterobacter cloacae, was examined using digital analysis of photographic evidence of necrosis as well as for carbohydrate, ethane, and ethylene
release compared with uninoculated potato tuber slices. Visual scoring of necrosis was superior to digital analysis of photographs.
The release of carbohydrates and ethane from potato tuber slices inoculated with the soft rot necrosis-causing Erwinia was significantly greater than that of potato tuber slices that had not been inoculated or that had been inoculated with
the nonpathogenic E. cloacae and Citrobacter sp. strains. Interestingly, ethylene production from potato slices left uninoculated or inoculated with the nonpathogenic
Citrobacter strain was 5- to 10-fold higher than with potato slices inoculated with the pathogenic Erwinia strain. These findings suggest that (1) carbohydrate release might be a useful measure of the degree of pathogenesis, or
relative virulence; and that (2) bacterial suppression of ethylene formation may be a critical step in root rot disease formation. 相似文献
5.
To facilitate molecular genetic studies of Streptomyces ambofaciens that produces spiramycin, a commercially important macrolide antibiotic used in human medicine against Gram-positive pathogenic
bacteria, the conditions for the conjugal transfer of DNA from E. coli to S. ambofaciens were established using a bacteriophage ϕC31 att/int system. The transconjugation efficiency of S. ambofaciens varied with the medium used; the highest frequency was obtained on AS-1 medium containing 10 mM MgCl2 without heat treatment of the spores. In addition, by cloning and sequencing the attB site, we identified that S. ambofaciens contains a single attB site within an ORF coding for a pirin homolog, and its attB site sequence shows 100% nt identity to the sequence of S. coelicolor and S. lividans, which have the highest efficiency in transconjugation using the ϕC31 att/int system. 相似文献
6.
Tamura M Togami J Ishiguro K Nakamura N Katsumoto Y Suzuki K Kusumi T Tanaka Y 《Plant cell reports》2003,21(5):459-466
Verbena (Verbena x hybrida), an important floricultural species, was successfully regenerated from stem segments on Murashige and Skoog's basal medium supplemented with thidiazuron and indole-3-acetic acid. A transformation system was developed using cvs. Temari Scarlet, Temari Sakura, Tapien Rose and TP-P2. Agrobacterium tumefaciens strain Agl0 harboring the sGFP gene was infected into stem segments. Transformation efficiency was improved by evaluating and manipulating the age of the plant material, the concentration of kanamycin in the medium during selection, and the length of the culture period in the dark. After 2-3 months of culture on the selection medium, GFP-positive shoots were obtained in all four of the cultivars tested. These shoots were successfully acclimated and set flowers within 2-3 months in a greenhouse. GFP was expressed in all of the organs including the floral parts. Stable genomic transformation was confirmed by Southern blot analysis. No morphological differences were observed between the transformed plants and their host plants. 相似文献
7.
8.
The new taxon Luteoamylascus aculeatus described in this article is proposed to accommodate two collections of a hypogeous ascomycete from central Spain, characterized by a tomentose yellowish peridium, labyrinth-like gleba filled with whitish hyphae, and intensely reacting amyloid asci. ITS, 28S, and RPB2 data suggest that this new taxon is an independent lineage proposed here as the new genus Luteoamylascus. Until now, this lineage was only known from ectomycorrhizal root tips and mitotic spore mats. In phylogenetic analyses, the Luteoamylascus lineage is placed close to the genera Amylascus, Pachyphlodes, and Scabropezia. Morphological data suggest an affinity with Amylascus. 相似文献
9.
K. Škrlep M. Bergant G. M. De Winter B. Bohanec J. Žel R. Verpoorte F. Van Iren M. Camloh 《Biologia Plantarum》2008,52(2):329-333
Different lines of cell suspension cultures of Taxus × media Rehd. and Taxus floridana Nutt. were cryopreserved with a two-step freezing method using a simple and inexpensive freezing container instead of a programmable
freezer. Four to seven days old suspension cell cultures were precultured in growth medium supplemented with 0.5 M mannitol
for 2 d. The medium was then replaced with cryoprotectant solution (1 M sucrose, 0.5 M glycerol and 0.5 M dimethylsulfoxide)
and the cells incubated on ice for 1 h. Before being plunged into liquid nitrogen, cells were frozen with a cooling rate of
approximately −1 °C per min to −80 °C. The highest post-thaw cell viability was 90 %. The recovery was line dependent. The
cryopreservation procedure did not alter the nuclear DNA content of the cell lines. The results indicate that cryopreservation
of Taxus cell suspension cultures using inexpensive freezing container is possible. 相似文献
10.
Background
Carotenoids are a group of C40 isoprenoid molecules that play diverse biological and ecological roles in plants. Tomato is an important vegetable in human diet and provides the vitamin A precursor β-carotene. Genes encoding enzymes involved in carotenoid biosynthetic pathway have been cloned. However, regulation of genes involved in carotenoid biosynthetic pathway and accumulation of specific carotenoid in chromoplasts are not well understood. One of the approaches to understand regulation of carotenoid metabolism is to characterize the promoters of genes encoding proteins involved in carotenoid metabolism. Lycopene β-cyclase is one of the crucial enzymes in carotenoid biosynthesis pathway in plants. Its activity is required for synthesis of both α-and β-carotenes that are further converted into other carotenoids such as lutein, zeaxanthin, etc. This study describes the isolation and characterization of chromoplast-specific Lycopene β-cyclase (CYC-B) promoter from a green fruited S. habrochaites genotype EC520061. 相似文献11.
C. violaceum appeared as important bacterium in different applications and mainly these aspects are related to the production of violacein.
This review discusses the last reports on biosynthetic pathways, production, genetic aspects, biological activities, pathological
effects, antipathogenic screening through quorum sensing, environmental effects and the products of C. violaceum with industrial interest. An important discussion is on biological applications in medicine and as industrial products such
as textile and in cosmetics. 相似文献
12.
Much attention has been focused on the study of lactoferrin at the protein or nucleotide level in mice, humans, and cattle, but little is known about it in goats. The goat LF gene from 5' UTR to exon 17 was amplified, and the variation of g.7605C→T in 10 Chinese indigenous goat breeds was analyzed. Among the three ruminant species (cattle, sheep, and goats), the intron-exon distribution pattern was similar, and all the exons had the same length, but the length of introns varied greatly due to insertions or deletions. The frequency of allele T at g.7605C→T (50.12%) was a little higher than that of allele C (49.88%), and the genotype distribution differed greatly between goat populations. The g.7605C→T site showed higher genetic diversity in goat populations. The genetic differentiation was 0.0783, and gene flow was 2.9433 among the 10 Chinese indigenous goat populations. 相似文献
13.
Four stereoisomers of 2-norbornyl-N–n-butylcarbamates are characterized as the pseudo substrate inhibitors of cholesterol esterase. Cholesterol esterase shows
enantioselective inhibition for enantiomers of exo- and endo-2-norbornyl-N–n-butylcarbamates. For the inhibitions by (R)-(+)- and (S)-(−)-exo-2-norbornyl-N–n-butylcarbamates, the R-enantiomer is 6.8 times more potent than the S-enantiomer. For the inhibitions by (R)-(+)- and (S)-(−)-endo-2-norbornyl-N–n-butyl-carbamates, the S-enantiomer is 4.6 times more potent than the R-enantiomer. The enzyme-inhibitor complex models have been proposed to explain these different enantioselectivities. 相似文献
14.
Our work is the first study on the vocal repertoire of one of the babbler species, Elliot’s laughingthrush. Field studies were carried out in Hupingshan Nature Reserve, Hunan Province, China. There are three types of signals in the repertoire: songs, calls (chattering), and duets. Songs and calls are used by both males and females. The song consists of a quiet introduction (short note) and a louder main part (two or three tonal notes). There are up to four song variants in the repertoire of a given pair. All songs can be classified into three types. Types I and II represent songs with the main part consisting of three notes, while type III consists of two notes. Types I and II differ from each other in certain features of the frequency modulation shape of the first two notes. All song types can be used during the spontaneous vocalization of a single bird. However, their usage in other contexts differs. Songs of types I and II are more often uttered during vocal interactions of neighbor males. Songs of type III appear to be characteristic of male–female duets. Chattering (calls) is a continuous series of broadband notes. There are several (two to five) note variants in each series. Chattering can be used both during a male–female interaction and as an alarm call. We found an inverse correlation between (1) the duration of pauses between notes, and (2) the number of note variants (“repertoire size”) in a series. Both parameters probably reflect the internal state of an individual at a given moment. 相似文献
15.
The reproductive characteristics and pollination system of Rhododendron semibarbatum were investigated at two sites in Honshu, Japan. This species is protandrous, partially self-incompatible at postzygotic
stages, and requires outcrossing via pollinator visitation for effective seed production. The effective pollinators were two
bumblebee species: males of Bombus ardens at Miyama, and workers of Bombus honshuensis at Agematsu. The flowers possess two staminodes ornamented with whitish hairs, which do not reflect UV light, on the filaments.
Nectar was secreted continuously during the flowering period, and nectar production rate differed between the sites. Visitation
by B. ardens males was more frequent and varied among and within days, whereas that by B. honshuensis workers was less frequent and constant throughout the observation period. A single visit by a B. ardens male was more effective for seed production than visitation by a B. honshuensis worker, resulting in pollen limitation in the latter case. Differences in resource requirements between the two pollinators,
representing different castes, might affect their behavior, resulting in B. ardens males contributing to more effective seed production.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
16.
Yu Long Min Tao Shaojun Liu Huan Zhong Lin Chen Suifei Tao Yun Liu 《Cell and tissue research》2009,338(1):151-159
Gonadotropin-releasing hormone (GnRH), gonadotropin hormone (GTH), and gonadotropin hormone receptor (GTHR) are the pivotal
signal molecules of the hypothalamic-pituitary-gonad (HPG) axis, which plays a crucial role in regulating gonadal development
in vertebrate. In this study, we comparatively analyze the expression characteristics of Gnrh2, Gthβ, and Gthr in red crucian carp diploids, triploids, and allotetraploids. The expression patterns of these genes are similar in the three
fish ploidy types: the Gnrh2 gene is expressed in midbrains, pituitaries, and gonads; the Gthβ gene is expressed in pituitaries; the Gthr gene is mainly expressed in gonads. These results indicate that the three genes participate in the regulation of gonadal
development. By real-time polymerase chain reaction and in situ hybridization, we find that, among these three fish ploidy
types, the expression level of Gthr in the gonads of triploids is lower than those of diploids and tetraploids; this weakens the combination of GTHR with GTH
released from the pituitary and leads to the sterility of triploids, since the gonad cannot produce enough sex steroids. In
addition, the low expression of Gthr in triploids may affect the down-regulation of Gthβ, which then affects the down-regulation of Gnrh2; hence, the expression levels of Gnrh2 and Gthβ genes in triploids are the highest after the breeding season. In conclusion, the differential expression of Gnrh2, Gthβ, and Gthr in triploids and tetraploids is related to their sterility and bisexual fertility, respectively. 相似文献
17.
In this study, we investigated the influence of cold stratification on seed germination in S. × niederederi, a hybrid between the North American S. canadensis and the European S. virgaurea, using fruit samples collected in 2016 in Poland. We aimed to test the hypothesis that the low temperature exposure decreases the final percentage and speed of seed germination in the hybrid and its parental species. For each species, sets of 100 achenes in three replications were mixed with dry sand and stored in Petri dishes in darkness for 12 weeks, at ?18 °C and?+?4 °C, and?+?25 °C. The seeds were incubated for 21 d at room temperature (+25 °C), under the 12 h photoperiod (630 lx). We showed a lack of significant differences in: (i) the final percentage of germinated seeds of studied species stored at the same conditions, (ii) the final percentage of germinated seeds between the applied stratification conditions in the hybrid and its parental species, and (iii) the mean values of Timson’s index, mean germination time, and coefficient of velocity of germination between the stratification conditions in each species. The statistically significant inter-specific differences in the mean germination time parameter after the +25 °C treatment suggest that the seeds of S. × niederederi are able to germinate faster than the seeds of its parental species. However, to improve our knowledge of naturalization and invasion abilities of S. × niederederi by sexual reproduction, the seed germination and seedling survival of the hybrid should be tested in the field. 相似文献
18.
Specific activities and isoform patterns of peroxidases, acid phosphatases, DNases and RNases were studied in relation to
in vitro rooting of Petunia × hybrida microshoots in the presence of 4 μM indole-3-butyric acid (IBA). Specific activities of the above enzymes increased in the
course of rooting. Rhizogenesis could be related with an increased specific activity of peroxidases during the initiation
phase, in parallel with increased lignin content. Twelve peroxidases, six anionic (A1–A6) and six cationic (C1–C6), seven
acid phosphatases (ACP1–ACP7), seven RNases (R1–R7) and four DNases (D1–D4) isoforms were detected following native PAGE.
Variation in the number of the above isoforms and their quantity was observed during different stages of rooting. Particularly,
A2, A3, C3, C4, C5, ACP2, R1, R2, R3, and D4 isoforms appeared after the induction phase and could be related to emergence
of root primordia. Additionally, R3 and D4 could be associated with cell division and differentiation, since these are only
expressed in rooted microshoots. Moreover, the higher number of roots in IBA-treated microshoots could be related to the higher
expression of RNase and DNase isoforms during initiation and expression phases. 相似文献
19.
L. Gigliarelli L. Lucentini A. Palomba G. Sgaravizzi H. Lancioni L. Lanfaloni P. Willenz E. Gaino F. Panara 《Hydrobiologia》2008,605(1):265-269
The two freshwater sponges Ephydatia fluviatilis and Ephydatia mülleri belong to the widespread Spongillidae family. Their morphological tracts are very similar and can be distinguished mainly
on the basis of their gemmuloscleres. However, when gemmules are absent it is essential to have an unambiguous species attribution
for a population genetic study based on fresh tissues and historical collections. This article reports a simple Polymerase
Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) analysis, applied to DNA extracted from both gemmules and
fresh tissues in order to discriminate between the two congeneric E. fluviatilis and E. mülleri. Such a biomolecular method is based on the discriminative enzymes’ digestion of each of the three amplified fragments 5.8S-ITS2-28S,
D3 domain of the 28S subunit and COI. Two restriction enzymes were tested for a 620–642 bp fragment of 5.8S-ITS2-28S and for
a 342 bp fragment of the D3 domain of the 28S, one restriction enzyme was tested for a 681 bp fragment codifying for COI.
Obtained digestion patterns were diagnostic for each of the two species, providing a relatively simple, fast and cheap method
for species attribution compared to sequencing.
Handling editor: C. Sturmbauer 相似文献
20.
Transformation of 2,4,6-trinitrotoluene (TNT) by <Emphasis Type="Italic">Raoultella</Emphasis> <Emphasis Type="Italic">terrigena</Emphasis> 总被引:1,自引:0,他引:1
Claus H Bausinger T Lehmler I Perret N Fels G Dehner U Preuss J König H 《Biodegradation》2007,18(1):27-35
Manufacture of nitroorganic explosives generates toxic wastes leading to contamination of soils and waters, especially groundwater.
For that reason bacteria living in environments highly contaminated with 2,4,6-trinitrotoluene (TNT) and other nitroorganic
compounds were investigated for their capacity for TNT degradation. One isolate, Raoultella terrigena strain HB, removed TNT at concentrations between 10 and 100 mg l−1 completely from culture supernatants under optimum aerobic conditions within several hours. Only low concentrations of nutrient
supplements were needed for the cometabolic transformation process. Radioactivity measurements with ring-labelled 14C–TNT detected about 10–20% of the initial radioactivity in the culture supernatant and the residual 80–90% as water-insoluble
organic compounds in the cellular pellet. HPLC analysis identified aminodinitrotoluenes (2-ADNT, 4-ADNT) and diaminonitrotoluenes
(2,4-DANT) as the metabolites which remained soluble in the culture medium and azoxy-dimers as the main products in the cell
extracts. Hence, the new isolate could be useful for the removal of TNT from contaminated waters. 相似文献