Molecular identification of <Emphasis Type="Italic">Ammonia</Emphasis> and <Emphasis Type="Italic">Elphidium</Emphasis> species (Foraminifera,Rotaliida) from the Kiel Fjord (SW Baltic Sea) with rDNA sequences

Ammonia and Elphidium collected in the Kiel Fjord for the present study were first identified on morphological bases as Ammonia beccarii (Linné, 1758) and Elphidium excavatum (Terquem, 1876). Phylogenetic analyses based on partial SSU rDNA and LSU rDNA sequences show that Ammonia specimens sampled in the Kiel Fjord belong to the phylotype T6, which has a disjunct distribution (Wadden and Baltic Seas/China and Japan) and has been identified as Ammonia aomoriensis (Asano, 1951). Partial SSU rDNA sequence analyses indicate that Elphidium specimens from the Kiel Fjord belong to the clade E. excavatum, confirming the morphological identification. This clade can be further divided in three subclades. Kiel Fjord Elphidium belong to two of these subclades and were identified morphologically as the subspecies E. excavatum excavatum (Terquem, 1876) and E. e. clavatum Cushman, 1930.     

Distribution patterns of the Diaptomidae (Calanoida: Copepoda) in southern Africa

All freshwater calanoids in southern Africa belong to the family Diaptomidae of which there are two subfamilies, the Paradiaptominae (Lovenula, Paradiaptomus and Metadiaptomus) and Diaptominae (Tropodiaptomus and Thermodiaptomus). The Paradiaptominae are endemic to Africa, while the Diaptominae have one endemic African genus Thermodiaptomus, and the other genus Tropodiaptomus, occurs in other parts of the world as well as Africa. Knowledge of distribution of the Diaptomidae has been hampered by incomplete taxonomic knowledge and lack of co-ordination of available information. Distribution patterns of 19 described species and 11 new species confirm that the majority of species have a limited distribution, and that the Paradiaptominae are arid-adapted and belong to temporary pool communities. Six species are endemic to coastal pans and vleis of the western and southern Cape Province. Only those species with a wider distribution have been recorded as colonising man-made lakes. The four Lovenula species are predators and often co-exist with a Metadiaptomus species as prey. Synapomorphies of widely separated species of the Paradiaptominae, provide interesting insights into how their evolution may have been governed by vicariance, dispersal and palaeoenvironments of the African continent.     

A Taxonomic Study of Strains Received as “Mycobacterium” rhodochrous

A taxonomic study was carried out on 20 strains received as “Mycobacterium” rhodochrous. These strains were exceedingly similar to the strains of the genus Gordona recently proposed by the present author. Out of the 20 strains studied, 10 strains, including two strains previously named Rhodococcus rhodochrous, formed one cluster and were considered to belong to a species of the genus Gordona. The species has been named Gordona rhodochroa (Zopf; Overbeck; Gordon et Mihm) Tsukamura comb. nov. Two strains were considered to belong to the species Gordona rubra. One of the two had initially been named Mycobacterium rubropertinctum. It was considered from the facts that the specific epithet for the species should be “rubropertinta” and the name Gordona rubra be changed to Gordona rubropertincta. The other strains seemed to belong to some other species. In conclusion, the species “Mycobacterium” rhodochrous appears to be divided into several species of the genus Gordona.     

Streptomyces thermonitrificans sp.n., a thermophilic streptomycete

A new species of thermophilicStreptomyces has been isolated from a soil sample collected in Bombay. Its morphological characteristics and physiological behaviour have been studied in detail. It has thus been found to belong to Series XVI-Thermophilus of Waksman's scheme of classification (1961). Its similarity to and differences from a few known species are described. It has been designated asStreptomyces thermonitrificans.     

Issue Information

Aeolidia papillosa (Linnaeus, 1761 ) is a well‐known aeolidiid species that has been reported to have a worldwide distribution in cold–temperate waters, mainly from the northern hemisphere. Molecular tools have recently shown that most cosmopolitan species usually belong to a taxonomic species complex. Here we used integrative taxonomy to test the range of distribution of A. papillosa, and to assess the existence of a putative species complex that has been traditionally included as a single species under the name A. papillosa. Maximum‐likelihood and Bayesian analyses of partial DNA sequences of the mitochondrial cytochrome c oxidase subunit I and 16S rRNA genes, and the nuclear gene histone 3, were used to infer phylogenetic trees. Automatic Barcode Gap Discovery (ABGD) species delimitation analyses and morphological study complemented the phylogenetic approach. Our results show that A. papillosa is a cosmopolitan and an amphi‐Atlantic species, being distributed in the eastern and western Atlantic as well as in the eastern Pacific; however, some specimens from the UK and the Netherlands, together with specimens from Portugal, Galicia, and France, as well as the Californian and Oregon populations, emerge as two pseudocryptic species described herein: Aeolidia filomenae  sp. nov. and Aeolidia loui  sp. nov. , respectively. Finally, the specimens from Chilean coasts, previously attributed to A. papillosa, belong to a different species, Aeolidia campbellii (Cunningham, 1871 ), that is a senior synonym of Aeolidia serotina Bergh, 1873 .     

REASSIGNMENT OF ASPIDIUM HETEROPHYLLUM TO A NEW GENUS IN THE FAMILY M ATONI ACE AE

A fossil fern described originally by W. Fontaine as Aspidium heterophyllum has been reexamined. Based upon characteristics of the sorus, indusium, sporangium, and spores the plant belongs to the family Matoniaceae. There is no genus within the family to which the fossil can be assigned; thus, a new genus (Delosorus) is proposed. This report increases the number of plants within the Lower Cretaceous Potomac Group that belong in the Matoniaceae.     

The NodI and NodJ proteins from Rhizobium and Bradyrhizobium strains are similar to capsular polysaccharide secretion proteins from Gram-negative bacteria

The NodI and NodJ nodulation proteins have been described in different Rhizobium and Bradyrhizobium species. The NodIJ genes belong to the nod regulon. Other genes from this regulon are involved in the biosynthesis and modification of lipo-oligosaccharide molecule(s) which are morphogénic signals when acting on legume roots. It has been proposed that the NodI and NodJ proteins belong to a bacterial inner membrane transport system of small molecules. Nucleotide sequencing of MudII PR 13 insertions in the nodulation region of the symbiotic plasmid from a Rhizobium leguminosarum bv. phaseoli strain CE3 has revealed the presence of NodI and nodJ related sequences downstream of nodC. Computer nucleotide sequence analysis of the entire NodI and NodJ sequences from R. leguminosarum bv. viciae and Bradyrhizobium japonicum strains show that both proteins are similar to the KpsT and KpsM proteins from Escherichia coli Kl and K5 strains, to the BexB and BexA proteins from Haemophilis influenzae and to the CtrD and CtrC proteins from Neisseria meningitidis, respectively. Except for the NodI and NodJ proteins, all of them have been involved in the mechanism of secretion of polysaccharides in each of their harbouring species. On the basis of the similarity found, we propose that the NodI and the NodJ proteins could be involved in the export of a lipo-oligosaccharide.     

Eretes diving beetles (Coleoptera: Dytiscidae) in Central Europe – witnesses of climate change?

Records of the predaceous diving beetles of the genus Eretes Laporte, 1833 (Coleoptera: Dytiscidae) in Central Europe are summarised. While old records from the beginning of the twentieth century from the Czech Republic, Hungary, and Romania belong to Eretes griseus (Fabricius, 1781), a species which has not been recaptured in Central Europe for nearly the last hundred years, recently collected specimens from Hungary and Slovakia belong to E. sticticus (Linnaeus, 1767) and represent its first records in these countries as well as in Central Europe. The first specimens were collected at light during hot summer nights and may document a recent spreading of the species from the Mediterranean. In addition, the occurrence of E. sticticus is formally confirmed in Bulgaria, Croatia, Greece, Israel, Libya, South European Territory of Russia, and Tunisia.     

The AAA motor complex of subunits CobS and CobT of cobaltochelatase visualized by single particle electron microscopy

Cobalamins belong to the tetrapyrrole family of prosthetic groups. The presence of a metal ion is a key feature of these compounds. In the oxygen-dependent (aerobic) cobalamin biosynthetic pathway, cobalt is inserted into a ring-contracted tetrapyrrole called hydrogenobyrinic acid a,c-diamide (HBAD) by a cobaltochelatase that is constituted by three subunits, CobN, CobS and CobT, with molecular masses of 137, 37 and 71 kDa, respectively. Based on the similarities with magnesium chelatase, cobaltochelatase has been suggested to belong to the AAA⁺ superfamily of proteins. In this paper we present the cloning of the Brucella melitensis cobN, cobS and cobT, the purification of the encoded protein products, and a single-particle reconstruction of the macromolecular assembly formed between CobS and CobT from negatively stained electron microscopy images of the complex. The results show for the first time that subunits CobS and CobT form a chaperone-like complex, characteristic for the AAA⁺ class of proteins. The molecules are arranged in a two-tiered ring structure with the six subunits in each ring organized as a trimer of dimers. The similarity between this structure and that of magnesium chelatase, as well as analysis of the amino acid sequences confirms the suggested evolutionary relationship between the two enzymes.     

The Escherichia coli BarA-UvrY two-component system is a virulence determinant in the urinary tract

Background  

The Salmonella enterica BarA-SirA, the Erwinia carotovora ExpS-ExpA, the Vibrio cholerae BarA-VarA and the Pseudomonas spp GacS-GacA all belong to the same orthologous family of two-component systems as the Escherichia coli BarA-UvrY. In the first four species it has been demonstrated that disruption of this two-component system leads to a clear reduction in virulence of the bacteria. Our aim was to determine if the Escherichia coli BarA-UvrY two-component system is connected with virulence using a monkey cystitis model.     

A new non-HLA multigene family associated with thePERB11 family within theMHC class I region

 In an effort to initiate steps designed to characterize the idiopathic hemochromatosis disease gene, the HLA-A/HLA-F region where this gene is in disequilibrium linkage with some polymorphic markers has been overlapped by a yeast artificial chromosome (YAC) contig. In order to achieve the physical mapping of these YACs and of the corresponding genomic region, we subcloned one of the YACs involved. A computer-assisted analysis of the sequence of one subclone led to the isolation of a potential exon that proved to belong to a new expressed messenger named HCGIX. After Southern blot analysis, the corresponding cDNA clone was found to belong to a new multigene family whose members are dispersed throughout the HLA class I region and are closely associated with members of another recently described multigene family designated PERB11. The data reported here suggest that these two multigene families form a cluster that have been dispersed together throughout the telomeric part of the major histocompatibility complex and have been involved in the genesis of this human class I region. Received: 23 February 1996 / Revised: 23 April 1996     

PFGE diversity within the methicillin-resistant <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> clonal lineage ST398

Background  

Livestock has recently been identified as a new reservoir of methicillin-resistant Staphylococcus aureus (MRSA). Most isolates belong to ST398 and are non-typeable with PFGE using SmaI, making it difficult to study transmission and outbreaks. Therefore, a new PFGE using Cfr9I, a neoschizomer of SmaI was optimized and evaluated to investigate ST398 isolates.     

Saccharopolyspora: an underexplored source for bioactive natural products

Actinomycetes are a rich source for secondary metabolites with a diverse array of biological activities. Among the various genera of actinomycetes, the genus Saccharopolyspora has long been recognized as a potential source for antibiotics and other therapeutic leads that belong to diverse classes of natural products. Members of the genus Saccharopolyspora have been widely reported from several natural sources including both terrestrial and marine environments. A plethora of this genus has been chemically investigated for the production of novel natural products with interesting pharmacological effects. Therefore, Saccharopolyspora is considered one of the pharmaceutical important genera that could provide further chemical diversity with potential lead compounds. In this review, the literature from 1976 until December 2018 was covered, providing a comprehensive survey of all natural products derived from this genus and their semi-synthetic derivatives along with their biological activities, whenever applicable. Moreover, the biological diversity of Saccharopolyspora species and their habitats were also discussed.     

The gene transformer-2 of Sciara (Diptera, Nematocera) and its effect on Drosophila sexual development

Background  

The gene transformer-2, which is involved in sex determination, has been studied in Drosophila, Musca, Ceratitis, Anastrepha and Lucilia. All these members of Diptera belong to the suborder Brachycera. In this work, it is reported the isolation and characterisation of genes transformer-2 of the dipterans Sciara ocellaris and Bradysia coprophila (formerly Sciara coprophila), which belong to the much less extensively analysed Sciaridae Family of the Suborder Nematocera, which is paraphyletic with respect to Suborder Brachycera.     

Purification,crystallization, and preliminary X-ray diffraction analysis of even-skipped homeodomain complexed to DNA

Embryonic development in metazoa, to a significant extent, is directed by genes which contain a conserved sequence motif named the homeobox. This sequence encodes a polypeptide called the homeodomain which has sequence specific DNA-binding activity. We report the purification, crystallization, and preliminary diffraction analysis of the Drosophila Even-skipped homeodomain (Eve HD) bound to two different oligonucleotides. Crystals of Eve HD complexed with an AT-rich sequence belong to space group P2₁, a = 34.06, b = 61.61, c = 39.99 Å, b=90.0°. These crystals diffract to at least 2.0 Å and both native and derivative data sets have been collected. Crystals of Eve HD complexed with a GC-rich sequence belong to space group P6₃, a = b = 124.52, c = 66.78 Å and diffract to 3.5 Å resolution. A native data set has been collected. © 1995 Wiley-Liss, Inc.     

Towards a phylogeny of the actinomycetes and related organisms

The method of 16S ribosomal RNA oligonucleotide cataloging has been used to establish phylogenetic relationships among a number of genera of actinomycetes and related organisms. The findings serve as a starting point for a restructuring of actinomycete taxonomy. Several genera, such asThermoactinomyces andEubacterium, do not belong with the group, and the species of at least one atypical genus,Micrococcus, must be included therein. The general tendency to classify within the group according to morphological complexity was shown to be phylogenetically invalid.     

The tardigrade Hypsibius dujardini, a new model for studying the evolution of development

Studying development in diverse taxa can address a central issue in evolutionary biology: how morphological diversity arises through the evolution of developmental mechanisms. Two of the best-studied developmental model organisms, the arthropod Drosophila and the nematode Caenorhabditis elegans, have been found to belong to a single protostome superclade, the Ecdysozoa. This finding suggests that a closely related ecdysozoan phylum could serve as a valuable model for studying how developmental mechanisms evolve in ways that can produce diverse body plans. Tardigrades, also called water bears, make up a phylum of microscopic ecdysozoan animals. Tardigrades share many characteristics with C. elegans and Drosophila that could make them useful laboratory models, but long-term culturing of tardigrades historically has been a challenge, and there have been few studies of tardigrade development. Here, we show that the tardigrade Hypsibius dujardini can be cultured continuously for decades and can be cryopreserved. We report that H. dujardini has a compact genome, a little smaller than that of C. elegans or Drosophila, and that sequence evolution has occurred at a typical rate. H. dujardini has a short generation time, 13–14 days at room temperature. We have found that the embryos of H. dujardini have a stereotyped cleavage pattern with asymmetric cell divisions, nuclear migrations, and cell migrations occurring in reproducible patterns. We present a cell lineage of the early embryo and an embryonic staging series. We expect that these data can serve as a platform for using H. dujardini as a model for studying the evolution of developmental mechanisms.     

中国地衣型子囊菌石耳科纲要

该纲要为东亚地衣型子囊菌石耳科研究的一部分.对于该科一些种的子囊盘进行了研究.     

Compartmentation of newly synthesized phosphatidylethanolamine in rat brain microsomes

Summary The compartmentation of the phosphatidylethanolamine newly synthesized in brain microsomesin vitro either by base exchange or net synthesis has been studied, using difluorodinitrobenzene as a chemical probe. The experimental results demonstrate that in rat brain microsomes the phosphatidylethanolamine molecules synthesized by base exchange and the bulk membrane lipid belong to different pools. Ca²⁺ bound to microsomes seems to be involved in the maintenance of the compartmentation of phosphatidylethanolamine. In the presence of Ca²⁺ the newly synthesized phosphatidylethanolamine molecules react with difluorodinitrobenzene as though they are organized in clusters. After biosynthesisin vivo orin vitro through the cytidine pathway, the compartmentation of the newly formed phosphatidylethanolamine appears less marked than after the synthesis through base exchange.     

Colletotrichum acutatum is the main cause of Colletotrichum leaf disease of rubber in Sri Lanka

Colletotrichum gloeosporoides has been described as the causal agent of Colletotrichum leaf disease of rubber in Sri Lanka and other parts of the world since 1905. A study carried out on vegetative and reproductive characteristics of 52 isolates from Colletotrichum leaf disease lesions on Hevea brasiliensis in Sri Lanka revealed that only 18 isolates belong to Colletotrichum gloeosporioides. The remaining 34 isolates represented C. aculatum indicating that C. acutatum is the main cause of Colletotrichum leaf disease in Sri Lanka.This revised version was published online in October 2005 with corrections to the Cover Date.