New Materials of Eriocaulon L. from China

This paper consists of a part of pertinent data obtained through a critical study of Eriocaulaceae from China. Included in it are three new series: Leiantha, Robustiora and Mangshanensia; seven new species: Eriocaulon acutibracteatum, E. angustulum, E. bilobatum, E. leianthum, E. sclerophyllum, E. glabri-petalum and E. mangshanense; five new varieties: E. rockianum var. latifolium, E. merrillii var. longibracteatum, E. sikokianum var. Linanense, E. alpestre var. sichanense and E. nantoense var. micropetalum; two new combinations: E. yaoshanense var. brevicalyx; E. nantoense var. parviceps; three new records in China: E. brownianum, E.brownianum var.nilagirense, E. zollingerianum; five: E. henryanum, E.pullum, E. yaoshanense, E. taishanense and E.faberi. In addition, fifteen taxon names are newly reduced to synonyms: E. yunnanense=E. brownianum; E. longifolium, E. sexangulare var. longifolium, E. sinii, E. kwangtungense and E. willdinovianum = E. sexangulare; E. setaceum var. capillus-naiadis= E. setaceum; E. filifolium = E. yaoshanense; E. suishaense, E. merrillii var. suishaense=E.merrillii; E. kengii=E.sikokianum; E. whangii=E.buergerianum; E. nipponicum, E. decemflorum var. nipponicum= E. decemflorum and E. nantoense var.trisectum = E. nantoense var.parviceps.     

New species of Elaphoglossum (Elaphoglossaceae) from northern South America

The fern genusElaphoglossum is well-represented in the Venezuelan pteridoflora with 98 species. Careful observation of the indument of rhizome and blade is necessary to distinguish the taxa. Thirty-three species and one variety are here describe as new:E. anceps, E. appressum, E. atrorubens, E. atrosquamatum, E. chrysopogon, E. crispatum var.crispatum, E. crispatum var.beitelii, E. delicatulum, E. dolichopus, E. drewianum, E. eriopus, E. floccosum, E. grallator, E. hieracioides, E. incubus, E. luteynii, E. maguirei, E. nigrocostatum, E. obovatum, E. ornithoglossum, E. ortegae, E. pilosius, E. praetermissum, E. stenoglossum, E. stergiossi, E. steyermarkii, E. styriacum, E. succubus, E. tachirense, E. tantalinum, E. urophyllum, E. vanderwerffii, E. vareschianum, andE. variolatum.     

Nineteen new species of Elaphoglossum (Elaphoglossaceae, Pteridophyta) from Bolivia

We describe and illustrate 19 new species ofElaphoglossum from Bolivia:E. ayopayaense, E. carrascoense, E. choquetangae, E. cotapatense, E. crispipalea, E. cruzense, E. elkeae, E. ellenbergianum, E. gonzalesiae, E. inquisitivum, E. madidiense, E. murinum, E. neei, E. palmarum, E. pannosum, E. paucinervium, E. puberulentum, E. pulchrum, andE. sunduei.     

A difference in optomotor behaviour of two Antarctic nototheniid fishes is correlated with the presence of a choroid<Emphasis Type="Italic"> rete mirabile</Emphasis> and Root effect

The hypothesis that fish vision is influenced by the presence of a choroid rete mirabile (an oxygen-concentrating apparatus in the eye) and the Root effect was tested using the optomotor response in two nototheniid species from Antarctica. Pagothenia borchgrevinki, an active cryopelagic zooplanktivore, does not exhibit a major Root effect and the rete is absent. In contrast, the sluggish, benthic nototheniid, Trematomus bernacchii, possesses both a rete and a significant Root effect. Whole-eye ocular PO2 was higher in T. bernacchii (18.6 kPa) than in P. borchgrevinki (18.1 kPa) and the optomotor response of T. bernacchii was positively influenced by subtended angle on a moving background whereas P. borchgrevinki did not respond to any subtended angle (0–600 min of arc). The optomotor response of T. bernacchii may therefore have been facilitated by elevated ocular PO2 due to the presence of the choroid rete and the Root effect.     

Citrate synthase from Antarctic ciliates: adaptation to low temperatures and comparison with temperate ciliates

The activity of citrate synthase (CS), a mitochondrial enzyme in the energy metabolism pathway, was studied in Euplotes focardii (Hypotrichia) and Uronema marinum (Scuticociliatia), isolated from samples of Antarctic seawater and, for comparison in E. vannus and U. nigricans, related ciliates from the Adriatic. The temperature-dependent characteristics of CS were investigated in the range 0–55°C, to evaluate mechanisms of thermal regulation, such as optimal temperature levels, activation energy, and kinetic parameters. CS activity was up to double that recorded in temperate organisms at reaction temperatures between 0 and 10°C. The optimal temperature for enzymatic activity was independent of Tamb. Activation energy for CS was significantly lower in Antarctic ciliates than in temperate ones, indicating a significant increase in the reaction rate. KM at various temperatures of the reaction substrates indicated the higher affinity of CS for acetyl-CoA in both Antarctic organisms at lower temperatures. The data for thermal profiles for KM, showing greater differences between E. focardii and E. vannus than between U. marinum and U. nigricans, support the distinctive physiological characteristics of each species. E. focardii is an endemic and psychrophilic species, whereas U. marinum is a typically ubiquitous species, more adaptable to environmental changes.     

广东樟木头5种桉树的能量特征研究

对广东省东莞市樟木头林场5种6 a生巨桉(Eucalyptus grandis)、柳桉(E.saligna)、大花序桉(E.cloeziana)、粗皮桉(E.pellita)和托里桉(E.torelliana)的能量特征进行研究.结果表明:5种桉树不同组分的灰分含量和热值存在显著差异(P<0.01).灰分含量为0.16%-8.37%,其中巨桉、柳桉、粗皮桉和托里桉均是叶>皮>枝>根>干,而大花序桉为皮>叶>枝>根>干;各组分的干重热值为15.12-18.85 kJ g~(-1),均以叶最高、皮最低,巨桉与粗皮桉为叶>枝>干>根>皮;柳桉与托里桉为叶>干>枝>根>皮;大花序桉为叶>枝>根>干>皮;去灰分热值为16.37～19.87 kJ g~(-1),除粗皮桉为叶>枝>皮>干>根外,其它4种各组分的去灰分热值均与干重热值的变化趋势相同.5种桉树的平均干重热值和去灰分热值分别以巨桉、粗皮桉最高,但均以托里桉最低.     

Nine new elaphoglossums (Elaphoglossaceae) from Mexico

Nine new species ofElaphoglossum are described from southern and western México:E. alan-smithii, E. decursivum, E. dissitifrons, E. leonardii. E. lepidopodum, E. mcvaughii, E. parduei, E. rzedowskii, andE. seminudum.     

Deciphering the mechanisms of HPV E6 mutations in the destabilization of E6/E6AP/p53 complex

In epithelial tumors, oncoprotein E6 binds with the ubiquitin ligase E6AP to form E6/E6AP heterodimer; then this heterodimer recruits p53 to form E6/E6AP/p53 heterotrimer and induces p53 degradation. Recent experiments demonstrated that three E6 single-site mutants (F47R, R102A, and L50E) can inhibit the E6/E6AP/p53 heterotrimer formation and rescue p53 from the degradation pathway. However, the molecular mechanism underlying mutation-induced heterotrimer inhibition remains largely elusive. Herein, we performed extensive molecular dynamics simulations (totally ～13 μs) on both heterodimer and heterotrimer to elucidate at an atomic level how each p53-degradation-defective HPV16 E6 mutant reduces the structural stabilities of the two complexes. Our simulations reveal that the three E6 mutations destabilize the structure of E6/E6AP/p53 complex through distinct mechanisms. Although F47R^E6 mutation has no effect on the structure of E6/E6AP heterodimer, it results in an electrostatic repulsion between R47^E6 and R290^p53, which is unfavorable for E6-p53 binding. R102A^E6 mutation destabilizes the structure of E6/E6AP heterodimer and significantly disrupts hydrophobic and cation-π interactions between F47^E6 and E286^p53/L298^p53/R290^p53. L50E^E6 mutation impairs both E6 interdomain interactions (especially F47-K108 cation-π interaction) and E6-E6AP intermolecular interactions important for the stabilization of E6/E6AP heterodimer. This study identifies the intra- and intermolecular interactions crucial for the complex stability, which may provide mechanistic insights into the inhibition of complex formation by the three HPV16 E6 mutations.     

Competition between strains ofBradyrhizobium japonicum for nodulation of soybeans at different nitrogen fertilizer levels

Competitive abilities of 3 strains ofBradyrhizobium japonicum (E104, E109, E110) for nodulation of soybean (Glycine max) at increasing nitrogen fertilizer levels were studied. Dry weight of plants nodulated by strain E110 were depressed at 10 g N·m^–2, the highest fertilizer level, even when mixed with strain E109. Strain E104 alone or mixed with E109 increased dry matter production. Strain E110 formed many dually infected nodules with strain E104 present but not with strain E109. However, strain E104 formed nodules containing strain E109. Neither strain E110 or E109 produced bacteriocin, so the incompatibility of these two strains had to be due to another reason. Strain E104 successfully competes with strain E109 but not with E110 at 10 g N·m^–2. It is concluded that strain E110 dominates the symbiotic relationships even if other strains are also present in the nodules. However, at a high N-fertilizer level strain E110 decreases the plant yield in contrast to E104, which could be recommended as inoculant at increased levels of soluble soil-N.     

Microsatellite Polymorphism and the Population Structure of the Black Tiger Shrimp (Penaeus monodon) in Thailand

: Genetic variation and differentiation of Thai Penaeus monodon from five geographic locations (Chumphon, Trad, Phangnga, Satun, and Trang) were investigated using five microsatellite loci (CUPmo18, Di25, Di27, CSCUPmo1, and CSCUPmo2). The number of alleles across the five loci ranged from 19 to 30, and heterozygosities ranged from 0.49 to 0.95. The mean number of alleles and effective number of alleles per locus were 21.0 to 26.6 and 13.1 to 20.4, respectively. The average heterozygosity across all investigated samples was 0.78, indicating high genetic diversity in this species. Geographic heterogeneity analysis of the results from two of the loci, CUPmo18 and Di25, showed significant differences among the Gulf of Thailand (Trad and Chumphon) but not the Andaman samples. Comparison between regions revealed significant heterogeneity of the Andaman and Trad P. monodon (P < .001), whereas those from Chumphon and the Andaman were genetically similar (P > .05). Significant genetic differentiation was consistently observed between the Andaman-Trad samples (FST = 0.0101, P < .0001) and the Chumphon-Trad samples (FST = 0.0101, P < .0001). On the basis of our analyses, the investigated samples from five geographic locations were allocated to three distinct populations composed of the Andaman Sea (A), Chumphon (B), and Trad (C).     

The proliferous species of Elaphoglossum (Elaphoglossaceae) and their relatives

Thirteen taxa of the fern genusElaphoglossum reproduce vegetatively by a bud borne at the retuse apex of the sterile frond. These and six of their nonproliferous close relatives, all of tropical America, are discussed and described. All but one belong to various species groups in the closely allied sectionsSetosa andUndulata, the remaining one belonging to sectionLepidoglossa. Fourteen of the taxa are new:E. boryanum var.eutecnum, E. cardioglossum, E. entecnum, E. exsertipes, E. herpestes, E. inciens, E. nanoglossum, E. omissum, E. phoras, E. phyllitidis, E. plumosum f. maternum, E. pseudoboryanum, E. rufum, andE. wardiae.     

Identification of polygyne and monogyne fire ant colonies (<Emphasis Type="Italic">Solenopsis invicta</Emphasis>) by multiplex PCR of <Emphasis Type="Italic">Gp-9</Emphasis> alleles

Summary. Oligonucleotide primers were designed to discriminate between the Gp-9^B and Gp-9^b alleles found in monogyne and polygyne colonies of fire ant, Solenopsis invicta Buren. Primers specific for the Gp-9^B allele produced a 517 bp amplicon and primers specific for Gp-9^b allele produced a 423 bp amplicon. When both sets of primers were multiplexed, homozygous monogyne ants produced a single 517 bp amplicon (specific for Gp-9^B), whereas heterozygous polygyne ants produced one 517 bp amplicon and one 423 bp amplicon (specific for Gp-9^B and Gp-9^b, respectively) which allowed the Gp-9 alleles to be discerned in a single reaction. This method was tested on ants from 20 monogyne colonies and 20 polygyne colonies and was 100% accurate in discriminating the two forms.     

A new method of quantitative determination of contamination of baker’s yeast by wild yeasts or by dissociation forms of the production culture

ПроизBодстBEнной КулBтурB? Л. АSлBeанКкeа Oписан ноBb?й Мeтод OпрEпEл?ния ЗАрАжEния коооEрчEскиx ПEкАрскиx ДрожжEй И ДрожжEBb?x ЗАтороB ДиКими щтАммАми ДрожжEй Или ДиссоциируЮщим-и формАми ПроиЗBодстBEнного щтАмоА. мEтод OсноBАн нА ПодАBлEний ПроизВодстBEнного штАммА 1 . 10–³ М— 3 . . 10–³ М КонцEнтрАциEй Монойодуксусной Кислеты и ПозBоляEт КоличEстBEнноE OцрEдEлEниE КонтАминАции (BырАжEнной OтношEниEм ЧислА СлучАEB ЗАражeния К Ч0438;слу Клeток ПроизBодстBeнного Штам043C;а) B Прeдeлex Пр Крайнeй Мeрe 1%     

Structural analysis reveals an amyloid form of the human papillomavirus type 16 E1--E4 protein and provides a molecular basis for its accumulation

The abundant human papillomavirus (HPV) type 16 E4 protein exists as two distinct structural forms in differentiating epithelial cells. Monomeric full-length 16E1^∧E4 contains a limited tertiary fold constrained by the N and C termini. N-terminal deletions facilitate the assembly of E1^∧E4 into amyloid-like fibrils, which bind to thioflavin T. The C-terminal region is highly amyloidogenic, and its deletion abolishes amyloid staining and prevents E1^∧E4 accumulation. Amyloid-imaging probes can detect 16E1^∧E4 in biopsy material, as well as 18E1^∧E4 and 33E1^∧E4 in monolayer cells, indicating structural conservation. Our results suggest a role for fibril formation in facilitating the accumulation of E1^∧E4 during HPV infection.     

The Sporulated Oocysts of Eimeria illinoisensis n. sp. and of Other Species of Eimeria of the Ox

SYNOPSIS. The sporulated oocysts of 12 species of Eimeria occurring in the ox Bos taurus in the United States are described and differentiated. They are E. alabamensis, E. auburnensis, E. bovis, E. brasiliensis, E. bukidnonensis, E. canadensis, E. cylindrica, E. ellipsoidalis, E. illinoisensis n. sp., E. subspherica, E. wyomingensis and E. zuernii. Two other species, not yet found in North America, which are recognized as valid are E. pellita and E. thianethi. The sporulated oocysts of E. illinoisensis n. sp. are ellipsoidal or slightly ovoid, 24–29 by 19–22 μ with a mean of 26.3 by 20.7 μ; their sporocysts are 13–16 by 6–7 μ with a mean of 15.3 by 6.5 μ. This species was found in 3 cattle from one farm in Illinois.     

THE GENOME CONSTITUTION AND PHYLOGENY OF ELYMUS AMBIGUUS

Two Elymus ambiguus Vasey & Scribn. collections from Utah and Idaho were 2n = 28, and the species behaved meiotically as an allotetraploid. The E. ambiguus plants were highly self-sterile, and they hybridized readily with Asian E. junceus Fisch. (2n = 14), E. karataviensis Roshev. (2n = 28), E. multicaulis Kar. & Kir. (2n = 28), and North American E. innovatus Beal (2n = 28). Chromosome pairing at metaphase-I in the E. ambiguus X E. junceus triploid hybrids indicated that one E. ambiguus genome was closely homologous with the E. junceus genome. Chromosome pairing in the tetraploid hybrids indicated that both E. ambiguus genomes were more or less homologous with the genomes of E. karataviensis, E. multicaulis, and E. innovatus. The basic genome formula of E. ambiguus may be written as JJXX, where J is the E. junceus genome and X is a genome of unknown origin. Chromosome pairing in the hybrids indicated that E. ambiguus is more closely related to North American E. innovatus than to the Asian species. The E. ambiguus X E. innovatus hybrids were the only hybrids that set seed. Gene flow between E. ambiguus and E. innovatus is biologically possible, but geographic separation of the species precludes natural introgression.     

Species novae generisEremostachys (Labiatae)

Five new species are described:Eremostachys codonocalyx from NE. Iran (related toE. subspicata),E. stenocalycina from NE. Afghanistan (related toE. alberti andE. hissarica),E. salangensis from NE. Afghanistan (close toE. bamianica),E. freitagii from E. Afghanistan (similar but not closely related toE. vulnerans), andE. andersii from E. Afghanistan (similar but not closely related toE. vulnerans), andE. andersii from NE. Afghanistan of isolated systematic position.

Florae Iranicae praecursores 5–9.     

Knock-down of both eIF4E1 and eIF4E2 genes confers broad-spectrum resistance against potyviruses in tomato

Background

The eukaryotic translation initiation factor eIF4E plays a key role in plant-potyvirus interactions. eIF4E belongs to a small multigenic family and three genes, eIF4E1, eIF4E2 and eIF(iso)4E, have been identified in tomato. It has been demonstrated that eIF4E-mediated natural recessive resistances against potyviruses result from non-synonymous mutations in an eIF4E protein, which impair its direct interaction with the potyviral protein VPg. In tomato, the role of eIF4E proteins in potyvirus resistance is still unclear because natural or induced mutations in eIF4E1 confer only a narrow resistance spectrum against potyviruses. This contrasts with the broad spectrum resistance identified in the natural diversity of tomato. These results suggest that more than one eIF4E protein form is involved in the observed broad spectrum resistance.

Methodology/Principal Findings

To gain insight into the respective contribution of each eIF4E protein in tomato-potyvirus interactions, two tomato lines silenced for both eIF4E1 and eIF4E2 (RNAi-4E) and two lines silenced for eIF(iso)4E (RNAi-iso4E) were obtained and characterized. RNAi-4E lines are slightly impaired in their growth and fertility, whereas no obvious growth defects were observed in RNAi-iso4E lines. The F1 hybrid between RNAi-4E and RNAi-iso4E lines presented a pronounced semi-dwarf phenotype. Interestingly, the RNAi-4E lines silenced for both eIF4E1 and eIF4E2 showed broad spectrum resistance to potyviruses while the RNAi-iso4E lines were fully susceptible to potyviruses. Yeast two-hybrid interaction assays between the three eIF4E proteins and a set of viral VPgs identified two types of VPgs: those that interacted only with eIF4E1 and those that interacted with either eIF4E1 or with eIF4E2.

Conclusion/Significance

These experiments provide evidence for the involvement of both eIF4E1 and eIF4E2 in broad spectrum resistance of tomato against potyviruses and suggest a role for eIF4E2 in tomato-potyvirus interactions.     

Differentiation of Erwinia Species in the "Amylovorap" Group by Class Analysis of Cellular Fatty Acids

Cellular fatty acids of Erwinia species in the Amylovora group ( E. amylovora, E. nigrifluens, E. quercina, E. rubrifaciens, E. salicis and E. tracheiphila ), grown on King's medium B agar for 1,3, and 6 days at 28°C, were analyzed by gas-liquid chromatography, grouped by chemical class, and compared in order to differentiate the species. For the group in general, the average percentage in 1-day-old cells ranged 36.4–41.5% for the saturated straight-chain even-carbon fatty acids, (Class A), 0.3–0.7% for saturated straight-chain odd-carbons (Class B), 43.4–53.3% for unsaturated acids (Class C), 4.5–7.1% for hydroxy-substituted acids (Class D), 0.2–2.0% for branched-chain acids (Class E), and 0–7.5% for cyclopropane fatty acids (Class F). Species could be differentiated in 4 sequential steps based on: 1) percentage of the 12:0 fatty acid ( E. amylovora >3.6%, E. quercina (1%);2) sum of Classes E + F ( E. tracheiphila (0.3%);3) ratio Class A/(E + F) ( E. salicis <8); and percentage of 18:1 ( E. rubrifaciens >14%, E. nigrifluens < 14%). Physiological age significantly affected relative percentages of Classes B, C and F in E. amylovora and E. salicis ; of Classes A, C and F in E. quercina ; of Class A in E. tracheiphila ; and of Class C in E. nigrifluens.