Sarcocystis inghami n. sp. (Sporozoa: Sarcocystidae) from the skeletal muscles of the Virginia opossum Didelphis virginiana in Michigan

This report describes the newly identified Sarcocystis inghami n. sp. from the skeletal muscles of opossums (Mammalia: Didelphidae) that were collected from south central Michigan (42° 43-42° 79N, 84° 18-84°mathtype="display">6'W), USA. The new species is distinguished from all species described from North and South American opossums by the distinctive morphology of the villar protrusions on the cyst wall. Sarcocysts of S. inghami are microscopic, up to 700 m long and 110 m wide. The sarcocyst wall is up to 7 m thick, with long, stalked protrusions which average 5.5 × 1.2 m. These are constricted at the base, expanded laterally, rounded off distally and occasionally bifid. The villar protrusions have numerous microtubules without electron–dense bodies that extend from the tips into the granular layer. Bradyzoites are 10.7 × 4.3 (8––12 × 4––5) m. This is the second species of Sarcocystis sarcocyst described from the Virginia opossum in North America.     

Postembryonic development ofParalabidocera antarctica (I. C. Thompson) (Copepoda,Calanoida) from the fast ice near Syowa Station,Antarctica

Six nauplius and five copepodid stages as well as adults ofParalabidocera antarctica (I. C. Thompson, 1898) (Copepoda:Calanoida) are described based on specimens obtained from fast ice and collected by a plankton net near Syowa Station (69°00 S, 39° 35 E), Antarctica. The adult male and female are redescribed in detail. Nauplius stages ofP. antarctica are very similar to the previously describedAcartia species. Sexual dimorphism becomes apparent from copepodid IV onwards in the morphology of antennule and leg 5. The copepodid stages of this species retain certain characteristics not only of Acartiidae but also of Pontellidae and Parapontellidae.     

Identification of the site of translational frameshifting required for production of the transposase encoded by insertion sequence IS 1.

Summary Previous genetic analyses indicated that translational frameshifting in the –1 direction occurs within the run of six adenines in the sequence 5-TTAAAAAACTC-3 at nucleotide positions 305–315 in IS 1, where the two out-of-phase reading frames insA and B-insB overlap, to produce transposase with a polypeptide segment Leu-Lys-Lys-Leu at residues 84–87. IS 1 mutants with a 1 by insertion, which encode mutant transposases with an amino acid substitution within the polypeptide segment at residues 84–87, did not efficiently mediate cointegration, except for an IS 1 mutant which encodes a mutant transposase with a Leu-Arg-Lys-Leu segment instead of Leu-LysLys-Leu. An IS 1 mutant with the DNA segment 5-CTTAAAAACTC-3 at positions 305–315 carrying the termination codon TAA in the B-insB reading frame could still mediate cointegration, indicating that codon AAA for Lys corresponding to second, third and fourth positions in the run of adenines is the site of frameshifting. The -galactosidase activity specified by several IS 1- lacZ fusion plasmids, in which B-insB is in-frame with lacZ, showed that the region 292–377 is sufficient for frameshifting. The protein produced by frameshifting from the IS 1-lacZ plasmid in fact contained the polypeptide segment Leu - Lys - Lys - Leu encoded by the DNA segment 5-TTAAAAAACTC-3, indicating that –1 frameshifting does occur within the run of adenines.     

Stable transfer and expression of chimeric genes in licorice (Glycyrrhiza uralensis) using an Ri plasmid binary vector

The pharmaceutically important plant, licorice (Glycyrrhiza uralenesis Fisher), was transformed with a binary vector system of an Ri plasmid, pRi15834, and a mini Ti vector, pGSGluc1, containing chimeric neo and gus genes. The transgenic state of transformed roots was confirmed by detection of agropine and mannopine and by Southern blot hybridization with T-DNA of pGSGluc1. One to three copies of T-DNA of pGSGluc1 was integrated into the genomic DNA of G. uralensis. The expression of chimeric neo and gus genes driven by TR 1 and 2 promoters, respectively, was demonstrated by enzymatic assays. Histochemical analysis showed that the chimeric TR2-gus gene was expressed specifically in phloem and pericycle tissues of the transformed licorice roots.Abbreviations NPT-II neomycin phosphotransferase II - neo NPT-II gene from Tn5 - GUS ß-glucuronidase - gus GUS gene from Escherichia coli - TR 1–2 genes 1 and 2 of TR-DNA of pTiAch5 - Rif rifampicin     

Effects of abscisic acid (ABA) and ABA analogs on freezing tolerance,low-temperature growth,and flowering in rapeseed

Brassica napus and B. campestris are grown in Western Canada in areas subject to unseasonable frosts. At the seedling stage, cultivars of Brassica are very sensitive to frosts of -2° to-5°C, which are either lethal or delay the development of the plant. Seedlings of B. napus and B. campestris, germinated and grown at 10°C (16-h photoperiod), were treated with a foliar spray of either 100 M racemic abscisic acid (ABA), 100 M of various ABA analogs, 0.1% acetone, or were untreated. Freeze tests indicated 2°C of frost tolerance could be gained in B. napus following an application of three ABA analogs. In B. campestris, three analogs also increased freezing tolerance approximately 1.5°C. The analogs 2,3 dihydro ABA and acetylenic divinyl methyl-ABA were effective in both species. Plant fresh weight and dry weight increased in treated plants relative to control or acetone-treated plants after 3 weeks at 10°C. The effect of frost and/or analog treatment on flowering was determined in both species. In B. campestris and B. napus, a mild frost advanced flowering by approximately 2 days compared with nonfrozen control plants. The promotive effect of frost on flowering decreased with increasing severity of the frost. Several of the analog treatments, particularly 2,3 dihydro ABA and acetylenic divinyl ABA, advanced flowering by 2–3 days in both species. The benefit of these ABA analog treatments on flowering was enhanced additionally by a mild frost. Plants treated with either ABA, 2,3 dihydro ABA, 2,3 acetylenic dihydro ABA, or acetylenic divinyl ABA flowered up to 5 days earlier than control plants.     

Catatropis hatcheri n. sp. (Digenea: Notocotylidae) from Heleobia hatcheri (Prosobranchia: Hydrobiidae) and notes on its life-cycle in Patagonia, Argentina

A new species of Catatropis Oghner, 1905 from a freshwater Neotropical prosobranch snail, Heleobia hatcheri (Hydrobiidae), is described. Naturally infected snails were collected from Nahuel Huapí Lake in Andean Patagonia. The characteristics of the larval stages are also presented. Experimental adults were recovered from the distal region of the intestinal caeca of chicks and ducklings and natural adults from a wild duck Anas platyrhynchos. Adults of Catatropis hatcheri n. sp. can be distinguished from all other species of the genus in having 10–12 (11) ventral glands in each lateral row, the cirrus-sac extending back to between the first third and the middle of the body, the metraterm shorter than the cirrus-sac, a previtelline field of 1,258–1,544 (1,396), vitelline follicles reach back to the anterior border of the testes with some follicles extending slightly lateral to them, only external testicular margin lobed and genital pore in median line just posterior to the intestinal bifurcation. In addition, the eggs have one filament on each pole, the rediae contain one or two mature cercariae, and the cercariae are tri-oculate, with a long tail and encyst in the environment.     

The sea anemone genus Actinostola Verrill 1883: variability and utility of traditional taxonomic features, and a re-description of Actinostola chilensis McMurrich 1904

Species of the genus Actinostola are known for high variability of features. Anatomy, histology and cnidae of type specimens of five species from South America and Antarctica originally described as members of Actinostola and one species of Stomphia were compared to specimens of Actinostola chilensis collected during this study. None of these traditionally used features clearly distinguish the examined Actinostola species. I therefore propose new distinctive taxonomic features, including in vivo and in situ data. I provide an emended diagnosis of the genus Actinostola and a revised list of its species. I accept the synonymy of A. excelsa, A. pergamentacea and A. intermedia with A. crassicornis, and reject the synonymy of A. chilensis with A. crassicornis and A. intermedia. I re-describe A. chilensis in detail, including in situ information. Specimens of A. chilensis inhabit exposed positions of rocky substrate from 22 m depth down in south Chilean fjords between Puerto Montt (41°3535S, 72°53W) and Puyuhuapi (44°3136S; 72°326W); the most conspicuous features are its relatively large size, bright-orange colour, smooth, tough column and numerous and clearly entacmaeic tentacles.Electronic Supplementary Material  Supplementary material is available in the online version of this article at The publisher regrets that during copy-editing of this article the names of the authors of species were styled incorrectly. Therefore, it was decided to publish this erratum which, due to the nature of the paper, contains the whole original article, but now with the names of species authors styled correctly.The online version of the original article can be found at     

The life cycle of Laminaria abyssalis (Laminariales,Phaeophyta) in culture

Laminaria abyssalis occurs in deep water in tropical latitudes of the Brazilian coast (19° 23 S, 38° 28 W to 22° 54 S, 42° 13 09 W). Its life cycle has been completed in the laboratory in seven months using different conditions of light and temperature. The gametophytic stage required for growth the low photon flux density of 1.2 ± 0.3 µmol m^–2 s^–1 and 18 °C, while the juvenile and adult sporophytes needed 15 µmol m^–2 s^–1 and 18 °C. The sporophytes became fertile at 23 °C. Our results showed that light and temperature are the main factors regulating the growth and life history of this species under the culture conditions tested.     

Continuous production of 5′-ribonucleotides from yeast RNA by hydrolysis with immobilized 5′-phosphodiesterase and 5′-adenylate deaminase

The production of 5-IMP and 5-GMP by enzymatic conversion from RNA using a continuous two packed-bed reactor was investigated. 5-Phosphodiesterase (5PD) and 5-adenylate deaminase (5AD) were immobilized in an acrylic resin to produce derivatives with about 15 U/g of support. The kinetic properties of the enzymes were described by Michaelis-Menten models: no significant differences were found in the K _m value of the free and immobilized 5AD (60 and 20 m, respectively), whereas for 5PD the K _m value was one order of magnitude higher for the immobilized enzyme (4.85 mg RNA/ml), probably due to diffusional limitations. Both enzymes remained stable after 8 h of use in a continuous packed-bed reactor whereas the half lives of the free enzymes were 193 min and 240 min at 40°C and 70°C for 5AD and 5PD, respectively. A procedure is proposed for the design of a continuous two packed-bed column process.F. Olmedo and F. Iturbe are with the Depto. de Alimentos y Biotecnologia, Facultad de Química, UNAM, México 04510, D.F., Mexico. J. Gomez-Hernández is with the Depto. de Biotecnología, UAM-1, Apdo. Postal 55-535, México 09340, D.F., Mexico. A. López-Munguía is with the Instituto de Biotecnología, Apartado Postal 510-3, Cuernavaca, Mor. 62271, Mexico     

Morphological studies of Ancyracanthopsis winegardi Wong & Anderson, 1990 (Nematoda: Acuarioidea) and larval stages of acuariid nematodes parasitic in Larus dominicanus Lichtenstein (Aves: Laridae) from Argentina

Ancyracanthopsis winegardi Wong & Anderson, 1990 (Nematoda: Acuarioidea) is described from Larus dominicanus Lichtenstein (Aves: Laridae) on the Southwest Atlantic coast (38° 42S, 59° 47W). The main character used to distinguish species of Ancyracanthopsis is the morphology of the ptilina. Thus, although the specimens described here have some differences in the morphology and size of the spicules and in the female genitalia, they were referred to A. winegardi because they have a very similar ptilina. This is the first record of a member of Ancyracanthopsis from larid birds and for A. winegardi in the Southwest Atlantic coast. We have also studied acuariid larvae found inhabiting the gizzard alongside adult specimens of A. winegardi. Among those larvae, two morphological groups were clearly distinguished. The first group was characterised by the absence of ptilina and the presence of spicular primordia and rectal cells (third-stage larvae). The second group could be distinguished by the presence of ptilina and partly-developed genitalia (fourth-stage larvae). In order to identify the larvae, a Principal Component Analysis was applied to morphometric data taken from the third-stage larvae. These results and the morphology of the partly-developed ptilina of the fourth-stage larvae indicated that the larval stages found in L. dominicanus appear to belong to Sciadiocara haematopodi, Cremonte, Navone & Etchegoin, 1999.     

Facile synthesis of 2′-substituted lactoses

Isopropylidenation of lactose with 2,2-dimethoxypropane in the presence ofp-toluenesulfonic acid gave two products, which were identified by¹H- and¹³C-NMR as 2,35,63,4-tri-O-isopropylidenelactose dimethyl acetal (1) and its 6-O-(2-methoxy)-isopropyl derivative (2). These products were used for the synthesis of 2-O-methyllactose (7), 2,6-di-O-methyllactose (9) and 2-O-benzyllactose (13).     

Ontogeny of the thymus in an antarctic teleost,Harpagifer sp. (Notothenioidei: Perciformes)

Summary The development of the thymus was examined in different stages of Harpagifer sp. from Signy Island (South Orkney Islands; 60°43S, 45°38W). The thymus was typical, both in position and structural development, of that observed in warmer-water teleosts. The infiltration of the thymic epithelia was not observed until 4 weeks post-hatch. Full development of the lymphoid organs was not achieved until the juvenile stage. Although an increased infiltration of the thymus, by sub-epithelial connective tissues and epithelial mucous cells, occurred in the juvenile and adult stages, there was no evidence of an advanced stage of thymic regression or involution in the adult Harpagifer. Thus a suppressive influence of the low temperature environment, on the onset and degree of thymic development and involution, was indicated in this species.The signy Island population of Harpagifer has been given the species name H. antarcticus (Prof. J.C. Hureau; personal communication)     

Notiz über das Vorkommen niederer Erdphycomyceten in der Antarktis

Zusammenfassung Aus fünf antarktischen Bodenproben von 60°45, 62°14 und 63°24 südlicher Breite wurden in 92 Ansätzen drei niedere Phycomyceten herausgeködert, nämlich Rhizophydium utriculare, Rhizophydium sphaerotheca und Hyphochytrium cf. catenoides. Sie alle sind auch von Standorten mit milderem Klima bekannt und Kosmopoliten.     

Annual growth of the cockle Clinocardium ciliatum in the Norwegian Arctic (Svalbard area)

The Svalbard Islands are influenced by warm Atlantic water in the south and west, and cold Arctic water in the east. Ice cover, and hence the location of the highly productive marginal ice zone, varies both intra and interannually. Part of the primary production accumulates on the bottom and is utilized by the benthos. In this study, the annual growth of the cockle Clinocardium ciliatum (Fabricius, 1780) from three sites in Svalbard waters is reported. Moffen, the site in the north (80° 01 N, 13° 48 E) is located in the northernmost areas influenced by Atlantic water. The Storfjorden site (77° 10 N, 20° 09 E) is situated in cold Arctic water masses, and the Bear Island site (74° 50 N, 18° 54 E) is in the Polar front area where Atlantic and Arctic water masses meet. Annual growth of cockles was analysed retrospectively by measuring external growth increments, which gave annual growth records from the 1970s to 1996. Shell height for age for different year classes was highest at the Storfjorden site, and lowest at Bear Island. Periods of high growth occurred at Storfjorden and Bear Island during the 1980s while the beginning of 1990s was characterized by low growth. At Moffen, growth was more variable between single years. Several factors are influencing the growth of C. ciliatum in the Svalbard area and growth cannot be coupled to only one environmental factor like ice cover.     

Food assimilation of a neotropical riverine detritivorous fish, Prochilodus lineatus, studied by fatty acid composition (Pisces, Curimatidae)

Food assimilation by the detritivorous fish Prochilodus lineatus, throughout a life cycle, was studied by means of fatty acid analysis. Fish length ranged from 2.7 to 55 cm and weight from 2 to 2670 g. Samples for fatty acid determination were taken from the mesenteric deposit in adults and from the whole fish in juveniles. Phyto and zooplankton, and superficial mud were also studied. Samples were taken from the principal channel of the Paraná River and lentic environments in its alluvial plain (60 ° 29W and 31 ° 40S). Fatty acids in the smaller fish (2.8–3.8 cm) indicated the assimilation of zoo and phytoplankton. Longer P. lineatus have a fat-deficient diet, particularly in polyunsaturated acids. At different stages of life, P. lineatus is adapted to different sources of food. When young, it eats zoo- and phytoplankton, becomes gradually detritivorous and has a series of adaptations of the digestive tract (morphological and histological) to enable it to assimilate detritus.     

Effects of abscisic acid and abscisic acid analogs on the induction of freezing tolerance of winter rye (Secale cereale L.) seedlings

The ability of abscisic acid (ABA) and abscisic acid analogs to induce freezing tolerance in fall rye (Secale cereale cv Puma) seedlings grown at nonhardening temperatures was investigated. Analogs were constructed with systematic alterations at C-1 (acid replaced with methyl ester, aldehyde or alcohol), at C-4, C-5 (trans double bond replaced with a triple bond), and at C-2, C-3 (double bond replaced with a single bond so that the side chain and C-2 methyl groups were cis). Freezing tolerance (LT₅₀) was determined 3, 4 and 6 days after the first of two consecutive applications of chemical (100 µM) to either the leaves or roots. All analogs were more effective when applied to the plant roots than when applied to the leaves. ABA, acetylenic ABA and 2,3-dihydroacetylenic ABA decreased the LT₅₀ from –3 °C (control) to –9 °C. Consistent structure-activity relationships were only detected following root application. No single functional group altered was absolutely required for activity. The effect of any given change to the molecule was modified by the presence of other functional groups. For example, substituting the double bond in the ring with a single bond decreased activity, but concomitant substitution of the trans double bond in the side chain with a triple bond restored activity. In general, analogs with a cis, trans side chain were more active initially but rapidly lost activity, whereas acetylenic analogs maintained or gained activity over the three sampling times. The application of gibberellin biosynthesis inhibitors (100 µM; tetcyclacis or mefluidide) did not increase freezing tolerance beyond that induced by ABA, either alone or in combination with ABA. It can be concluded that ABA and certain ABA analogs can induce limited freezing tolerance in whole rye seedlings, and partially substitute for low temperature acclimation.     

Determination of the populations and structures of multiple conformers in an ensemble from NMR data: Multiple-copy refinement of nucleic acid structures using floating weights

A new algorithm is presented for determination of structural conformers and their populations based on NMR data. Restrained Metropolis Monte Carlo simulations or restrained energy minimizations are performed for several copies of a molecule simultaneously. The calculations are restrained with dipolar relaxation rates derived from measured NOE intensities via complete relaxation matrix analysis. The novel feature of the algorithm is that the weights of individual conformers are determined in every refinement step, by the quadratic programming algorithm, in such a way that the restraint energy is minimized. Its design ensures that the calculated populations of the individual conformers are based only on experimental restraints. Presence of internally inconsistent restraints is the driving force for determination of distinct multiple conformers. The method is applied to various simulated test systems. Conformational calculations on nucleic acids are carried out using generalized helical parameters with the program DNAminiCarlo. From different mixtures of A- and B-DNA, minor fractions as low as 10% could be determined with restrained energy minimization. For B-DNA with three local conformers (C2-endo, O4-exo, C3-endo), the minor O4-exo conformer could not be reliably determined using NOE data typically measured for DNA. The other two conformers, C2-endo and C3-endo, could be reproduced by Metropolis Monte Carlo simulated annealing. The behavior of the algorithm in various situations is analyzed, and a number of refinement protocols are discussed. Prior to application of this algorithm to each experimental system, it is suggested that the presence of internal inconsistencies in experimental data be ascertained. In addition, because the performance of the algorithm depends on the type of conformers involved and experimental data available, it is advisable to carry out test calculations with simulated data modeling each experimental system studied.     

Oxidative phosphorylation in membrane vesicles of a gram-positive methylotroph

Membrane preparations, capable of high rates of respiration-linked ATP synthesis, have been obtained from a gram-positive methylotrophic bacterium Bacillus sp. MGA3. NADH, succinate, reduced TMPD and methanol were shown to be suitable substrates for the oxidative phosphorylation. Esterification of orthophosphate was dependent on electron transfer, as evidenced by the requirement for both substrate and oxygen. Phosphorylation was also dependent on ADP and was destroyed by boiling the membrane preparation. The phosphorylation was markedly uncoupled by carbonyl cyanide p-(trichloromethoxy)-phenylhydrazone (CCCP) and was inhibited by N,N-dicyclohexylcarbodiimide (DCCD). KCN caused strong inhibition of substrate oxidation as well as phosphorylation for all substrates tested. Rotenone, amytal and antimycin A caused inhibition when NADH or methanol were used as substrates. Antimycin A inhibited respiration and ATP synthesis with succinate as substrate and had no effect on ascorbate —N,N,N,N-tetramethyl-p-phenylenediimide (TMPD) oxidation by membrane preparations of Bacillus sp. MGA3. P/O ratios determined were 2.4 with NADH, 1.7 with succinate and 0.8 with reduced TMPD. The measured P/O ratio with methanol-oxidizing system was similar to that with NADH (about 2.4).Abbreviations CCCP Carbonyl cyanide p-(trichloromethoxy)-phenylhydrazone - DCCD N,N-dicyclohexylcarbodiimide - TMPD N,N,N,N-tetramethyl-p-phenylenediimide - Q ubiquinone Q     

Pyridoxal 5′-phosphate binds to a lysine residue in the adenosine 3′-phosphate 5′-phosphosulfate recognition site of glycolipid sulfotransferase from human renal cancer cells

In the course of characterization of glycolipid sulfotransferase from human renal cancer cells, the manner of inhibition of sulfotransferase activity with pyridoxal 5-phosphate was investigated. Incubation of a partially purified sulfotransferase preparation with pyridoxal 5-phosphate followed by reduction with NaBH₄ resulted in an irreversible inactivation of the enzyme. When adenosine 3-phosphate 5-phosphosulfate was co-incubated with pyridoxal 5-phosphate, the enzyme was protected against this inactivation. Furthermore, pyridoxal 5-phosphate was found to behave as a competitive inhibitor with respect to adenosine 3-phosphate 5-phosphosulfate with aK _i value of 287 µm. These results suggest that pyridoxal 5-phosphate modified a lysine residue in the adenosine 3-phosphate 5-phosphosulfate-recognizing site of the sulfotransferase.     

A comparison of line transect versus linear percentage sampling for evaluating stony coral (Scleractinia andMilleporina) community similarity and area coverage on reefs of the central Bahamas

Three methods of evaluating stony coral communities were used on selected reefs in the Exuma Cays Land and Sea Park (24°22N, 77°30W) in the central Bahamas. Shallow reefs (< 4 meters depth) were selected from aerial surveys based on size, location, and physical setting, and grouped into three community types: (1) channel patch reefs, (2) soft-coral-sponge patch reefs and (3) fringing reefs. Three survey techniques used to evaluate the stony coral communities were a) species presence and absence lists, b) linear percentage and c) line transects using 1 mx1 m grids. Data collected from these survey methods was used to calculate coral colony density, species area coverage, and species diversity based on colony number and based on linear (cm) coral cover. The linear percentage sampling was considered too convervative in determining distribution patterns of a reef community; this technique takes into account the massive reef framework species such asM. annularis. The line transect technique can account for both colony number and area coverage, thus is a better method for characterizing reef communities. Sample size considerations are discussed for future applications of survey techniques for ground-truthing digital images of small, shallow reef communities.