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1.
Six species of Gastrocopta have been identified from the Pilbara region, Western Australia, by means of comparative analyses of shell and mtDNA variation. Three of these species, Gastrocopta hedleyi, Gastrocopta larapinta and Gastrocopta servilis, have been recorded in the Pilbara for the first time. Gastrocopta sp. CW1 is probably new to science and might be endemic to the region. By contrast, Gastrocopta hedleyi, Gastrocopta larapinta and Gastrocopta mussoni are shown to be widespread. 相似文献
2.
Here we describe and illustrate a new parasitoid wasp species, Lathrolestes gauldi
sp. n. from the lowland rainforest of eastern Ecuador and provide a key to the Neotropical species of the genus. This is the first record of the subfamily Ctenopelmatinae from Ecuador. 相似文献
3.
Duvalius (sg. Neoduvalius) gejzadunayi
sp. n. from Pećina u Dubokom potoku cave ( Donje Biševo village near Rožaje, Montenegro), the first known representative of this subgenus from the territory of Montenegro is described, illustrated and compared with the related species of the subgenus Neoduvalius Müller, 1913. This new species is characterised by depigmented, medium sized body, totally reduced eyes, deep and complete frontal furrows, 3–4 pairs of discal setae in third elytral stria, as well as by the shape of aedeagus. Data on the distribution and the ecology of this remarkable species, as well as a check-list of the subgenus Neoduvalius are also provided. Recently described genera Serboduvalius Ćurčić, S. B. Pavićević & Ćurčić, B.P.M., 2001, Rascioduvalius Ćurčić, S. B. Brajković, Mitić & Ćurčić, B.P.M., 2003, Javorella Ćurčić, S. B. Brajković, Ćurčić, B.P.M. & Mitić, 2003 and Curcicia Ćurčić, S. B. & Brajković, 2003 are regarded as junior synonyms of the genus Duvalius Delarouzée. 相似文献
4.
The tiger beetle fauna of the Balkan Peninsula is one of the richest in Europe and includes 19 species or 41% of the European tiger beetle fauna. Assembled by their biogeographical origins, the Balkan tiger beetle species fall into 14 different groups that include, Mediterranean, Middle Oriental, Central Asiatic, Euro-Siberian, South and East European, Pannonian-Sarmatian, West Palaearctic, Turano-European and Afrotropico Indo-Mediterranean species. The Mediterranean Sclerophyl and the Pontian Steppe are the Balkan biogeographical provinces with the highest species richness, while the Balkan Highlands has the lowest Cicindelidae diversity. Most species are restricted to single habitat types in lowland areas of the Balkan Peninsula and only Calomera aulica aulica and Calomera littoralis nemoralis occur in respectively 3 and 4 different types of habitat. About 60% of all Balkan Cicindelidae species are found in habitats potentially endangered by human activity. 相似文献
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Background
Despite accelerated global population declines due to targeted and illegal fishing pressure for many top-level shark species, the impacts of coastal habitat modification have been largely overlooked. We present the first direct comparison of the use of natural versus artificial habitats for the bull shark, Carcharhinus leucas, an IUCN ‘Near-threatened’ species - one of the few truly euryhaline sharks that utilises natural rivers and estuaries as nursery grounds before migrating offshore as adults. Understanding the value of alternate artificial coastal habitats to the lifecycle of the bull shark is crucial for determining the impact of coastal development on this threatened but potentially dangerous species.Methodology/Findings
We used longline surveys and long-term passive acoustic tracking of neonate and juvenile bull sharks to determine the ontogenetic value of natural and artificial habitats to bull sharks associated with the Nerang River and adjoining canals on the Gold Coast, Australia. Long-term movements of tagged sharks suggested a preference for the natural river over artificial habitat (canals). Neonates and juveniles spent the majority of their time in the upper tidal reaches of the Nerang River and undertook excursions into adjoining canals. Larger bull sharks ranged further and frequented the canals closer to the river mouth.Conclusions/Significance
Our work suggests with increased destruction of natural habitats, artificial coastal habitat may become increasingly important to large juvenile bull sharks with associated risk of attack on humans. In this system, neonate and juvenile bull sharks utilised the natural and artificial habitats, but the latter was not the preferred habitat of neonates. The upper reaches of tidal rivers, often under significant modification pressure, serve as nursery sites for neonates. Analogous studies are needed in similar systems elsewhere to assess the spatial and temporal generality of this research. 相似文献8.
Knapp S 《PLoS biology》2011,9(5):e1001067
Assessment of conservation status is done both for areas or habitats and for species (or taxa). IUCN Red List categories have been the principal method of categorising species in terms of extinction risk, and have been shown to be robust and helpful in the groups for which they have been developed. A recent study highlights properties associated with extinction risk in flowering plants, focusing on the species-rich hot spot of the Cape region of South Africa, and concludes that merely following methods derived from studies of vertebrates may not provide the best estimates of extinction risk for plants. Biology, geography, and history all are important factors in risk, and the study poses many questions about how we categorise and assess species for conservation priorities. 相似文献
9.
The genus Tinissa Walker is reviewed for China. Seven species are recognized, of which Tinissa apicimaculata
sp. n., Tinissa conchata
sp. n., Tinissa connata
sp. n.,Tinissa leguminella
sp. n. and Tinissa spirella
sp. n. are described as new; and Tinissa insularia Robinson, 1976 is newly recorded from China. Photographs of the adults and illustrations of the genitalia are given. A key to all the known Chinese species and a distribution map of Tinissa in China are included. 相似文献
10.
A new species of copepod, Sarcotretes umitakae
sp. n., of the siphonostomatoid family Pennellidae is described based on female specimens from the rattail Coelorinchus jordani Smith and Pope (Actinopterygii: Gadiformes: Macrouridae) caught in the East China Sea. This species is characterized by exhibiting the following characters: the large proboscis projects strongly; the head bears paired lateral processes which are bulbous and taper into a slender horn; the twisting neck is significantly longer than the trunk; and the trunk bears an anterior constriction with a reduced abdomen. 相似文献
11.
Nidhi Ahuja Dmitry Korkin Rachna Chaba Brent O. Cezairliyan Robert T. Sauer Kyeong Kyu Kim Carol A. Gross 《The Journal of biological chemistry》2009,284(8):5403-5413
The Escherichia coli envelope stress response is controlled by the
alternative sigma factor, σE, and is induced when unfolded
outer membrane proteins accumulate in the periplasm. The response is initiated
by sequential cleavage of the membrane-spanning antisigma factor, RseA. RseB
is an important negative regulator of envelope stress response that exerts its
negative effects onσE activity through its binding to RseA.
In this study, we analyze the interaction between RseA and RseB. We found that
tight binding of RseB to RseA required intact RseB. Using programs that
performed global and local sequence alignment of RseB and RseA, we found
regions of high similarity and performed alanine substitution mutagenesis to
test the hypothesis that these regions were functionally important. This
protocol is based on the hypothesis that functionally dependent regions of two
proteins co-evolve and therefore are likely to be sequentially conserved. This
procedure allowed us to identify both an N-terminal and C-terminal region in
RseB important for binding to RseA. We extensively analyzed the C-terminal
region, which aligns with a region of RseA coincident with the major RseB
binding determinant in RseA. Both allele-specific suppression analysis and
cysteine-mediated disulfide bond formation indicated that this C-terminal
region of similarity of RseA and RseB identifies a contact site between the
two proteins. We suggest a similar protocol can be successfully applied to
pairs of non-homologous but functionally linked proteins to find specific
regions of the protein sequences that are important for establishing
functional linkage.The Escherichia coli σE-mediated envelope stress
response is the major pathway to ensure homeostasis in the envelope
compartment of the cell
(1-3).
σE regulon members encode periplasmic chaperones and
proteases, the machinery for inserting β-barrel proteins into the outer
membrane and components controlling the synthesis and assembly of LPS
(4-6).
This pathway is highly conserved among γ-proteobacteria
(6).The σE response is initiated when periplasmic protein
folding and assembly is compromised
(7-9).
During steady state growth, σE is inhibited by its antisigma
factor, RseA, a membrane-spanning protein whose cytoplasmic domain binds to
σE with picomolar affinity
(10-13).
Accumulation of unassembled porin monomers serves as a signal to activate the
DegS protease to cleave RseA in its periplasmic domain
(14,
15). This initiates a
proteolytic cascade in which RseP cleaves periplasmically truncated RseA near
or within the cytoplasmic membrane to release the
RseAcytoplasmic-σE complex, and cytoplasmic
ATP-dependent proteases complete the degradation of RseA thereby releasing
active σE
(16-19).RseB, a second negative regulator of the envelope stress response
(11,
20,
21), binds to the periplasmic
domain of RseA with nanomolar affinity. RseB is an important regulator of the
response (2,
22,
23). It prevents RseP from
degrading intact RseA, thereby ensuring that proteolysis is initiated only
when the DegS protease is activated by a stress signal
(21). Additionally, RseB
prevents activated DegS from cleaving RseA, suggesting that interaction of
RseB with RseA must be altered before the signal transduction cascade is
activated (23).The goal of the present studies was to explore how RseB binds to RseA. The
interaction partner of RseB is the unstructured periplasmic domain of RseA
(RseA-peri). Within RseA-peri, amino acids ∼169-186 constitute a major
binding determinant to RseB
(23,
24). This peptide alone binds
RseB with 6 μm affinity, and deleting this region abrogates
binding to RseB (23).
Additional regions of RseA-peri also contribute to RseB binding, as intact
RseA-peri binds with 20 nm affinity to RseB
(23). Much less is known about
the regions of RseB required for interaction with RseA. RseB is homodimeric
two-domain protein, whose large N-terminal domain shares structural homology
with LolA, a protein that transports lipoproteins to outer membrane
(24,
25). The smaller C-terminal
domain is connected to the N-terminal domain by a linker, and the two domains
share a large interface, which may facilitate interdomain signaling.
Glutaraldehyde cross-linking studies indicate that the C-terminal domain
interacts with RseA, but the regions of interaction were not identified
(25).In the present report, we study the interaction of RseB and RseA. We
establish that both domains of RseB interact with RseA-peri. Using a global
sequence alignment, we discovered several regions in RseA and RseB that had
high sequence similarity, despite the low overall sequence similarity between
these two proteins, a finding that was independently confirmed by a local
sequence similarity algorithm. This suggested that these regions were
functionally dependent, and we performed a set of mutagenesis experiments
designed to test this idea. Our studies of the binding properties of these
mutants revealed that regions in both the N terminus and C terminus of RseB
modulate interaction with RseA. Moreover, genetic suppression analysis and
cysteine-mediated disulfide bond formation suggest that the region of RseA/B
with highest similarity (RseA residues 165-191 (major binding determinant in
RseA) and RseB residues 233-258) are interacting partners. 相似文献
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13.
14.
16.
Alejandro Escánez Pérez Rodrigo Riera Elena ángel Francisco González González ángel Guerra Sierra 《ZooKeys》2012,(222):69-76
Data on opportunistic sightings of diamond-shaped squid Thysanoteuthis rhombus egg masses in the Canary Islands (Atlantic Ocean) are presented. A total of 16 egg masses of this species were recorded and photographed from 2000 to 2010 around the western islands of the archipelago (El Hierro, Tenerife and La Gomera). These data reveal the existence of an important spawning area for diamond-shaped squid around the Canary Islands, in subtropical east Atlantic waters. We provide preliminary data for the potential development of an artisanal fishery focused on this species, and a discussion on its potential impacts on the marine ecosystem. 相似文献
17.
Cleoni Alves Mendes de Lima Harrison Magdinier Gomes Maraníbia Aparecida Cardoso Oelemann Jesus Pais Ramos Paulo Cezar Caldas Carlos Eduardo Dias Campos Márcia Aparecida da Silva Pereira Fátima Fandinho Onofre Montes Maria do Socorro Calixto de Oliveira Philip Noel Suffys Maria Manuela da Fonseca Moura 《Memórias do Instituto Oswaldo Cruz》2013,108(4):457-462
The main cause of pulmonary tuberculosis (TB) is infection with
Mycobacterium tuberculosis (MTB). We aimed to evaluate the
contribution of nontuberculous mycobacteria (NTM) to pulmonary disease in
patients from the state of Rondônia using respiratory samples and
epidemiological data from TB cases. Mycobacterium isolates were identified using
a combination of conventional tests, polymerase chain reaction-based restriction
enzyme analysis of hsp65 gene and hsp65 gene
sequencing. Among the 1,812 cases suspected of having pulmonary TB, 444 yielded
bacterial cultures, including 369 cases positive for MTB and 75 cases positive
for NTM. Within the latter group, 14 species were identified as
Mycobacterium abscessus, Mycobacterium
avium, Mycobacterium fortuitum,
Mycobacterium intracellulare, Mycobacterium
gilvum, Mycobacterium gordonae,
Mycobacterium asiaticum, Mycobacterium
tusciae, Mycobacterium porcinum,
Mycobacterium novocastrense, Mycobacterium
simiae, Mycobacterium szulgai,
Mycobacterium phlei and Mycobacterium
holsaticum and 13 isolates could not be identified at the species
level. The majority of NTM cases were observed in Porto Velho and the relative
frequency of NTM compared with MTB was highest in Ji-Paraná. In approximately
half of the TB subjects with NTM, a second sample containing NTM was obtained,
confirming this as the disease-causing agent. The most frequently observed NTM
species were M. abscessus and M. avium and
because the former species is resistant to many antibiotics and displays
unsatisfactory cure rates, the implementation of rapid identification of
mycobacterium species is of considerable importance. 相似文献
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19.
Ana PM Oliveira Rosana Gentile Arnaldo Maldonado Júnior Eduardo J Lopes Torres Silvana C Thiengo 《Memórias do Instituto Oswaldo Cruz》2015,110(6):739-744
The aim of this study was to analyse the infection dynamics ofAngiostrongylus
cantonensis in its possible intermediate hosts over two years in an urban
area in the state of Rio de Janeiro where the presence ofA.
cantonensis had been previously recorded in molluscs. Four of the seven
mollusc species found in the study were exotic.Bradybaena similaris
was the most abundant, followed byAchatina fulica,
Streptaxis sp., Subulina octona,
Bulimulus tenuissimus, Sarasinula linguaeformis
and Leptinaria unilamellata. Only A. fulica
and B. similaris were parasitised by A.
cantonensis and both presented co-infection with other helminths. The
prevalence of A. cantonensisin A. fulica was more
than 50% throughout the study. There was an inverse correlation between the
population size ofA. fulica and the prevalence of A.
cantonensis and abundance of the latter was negatively related to
rainfall. The overall prevalence of A. cantonensis in B.
similariswas 24.6%. A. fulica was the most important
intermediary host of A. cantonensis in the studied area
andB. similaris was secondary in importance for A.
cantonensis transmission dynamics. 相似文献
20.
Fernando Fonseca Val Vanderson Souza Sampaio Maria Belén Cassera Raquel Tapajós Andrade Pedro Luiz Tauil Wuelton Marcelo Monteiro Marcus Vinícius Guimar?es Lacerda 《Memórias do Instituto Oswaldo Cruz》2014,109(5):522-524
In the 1950s, the strategy of adding chloroquine to food salt as a prophylaxis
against malaria was considered to be a successful tool. However, with the development
of Plasmodium resistance in the Brazilian Amazon, this control
strategy was abandoned. More than 50 years later, asexual stage resistance can be
avoided by screening for antimalarial drugs that have a selective action against
gametocytes, thus old prophylactic measures can be revisited. The efficacy of the old
methods should be tested as complementary tools for the elimination of malaria. 相似文献