Silurian graptolite biostratigraphy of the Röstånga-1 drill core, Scania:a standard for southern Scandinavia

The Rostanga-1 core from west-central Scania provides the most complete succession of the Sandbian (Upper Ordovician) through lower Telychian (Silurian, Llandovery) strata of southern Scandinavia. The Hirnantian is identified in the Kallholn Formation by the presence of a Metabolograptus persculptus Biozone fauna. The Akidograptus ascensus, Parakidograptus acuminatus, Cystograptus vesiculosus and Monograptus revolutus biozones can be differentiated in the Rhuddanian. Following a considerable gap (Demirastrites triangulatus Biozone to a level within the Pribylograptus leptotheca Biozone), the succession resumes. The Aeronian also includes the Lituigraptus convolutus and Stimulograptus sedgwickii biozones. The Stimulograptus halli Biozone appears to be missing, but the Telychian Spirograptus guerichi to Streptograptus crispus biozones have been recognized

Culture of Selected Microalgae in Rubber and Palm Oil Mill Effluents and their Use in the Production of Enriched Rotifers

Three freshwater microalgae Chlorella vulgaris, Selellastrum gracile and Ankistrodesmus convolutlls showed high growth performances in terms of specific growth rate (SGR) of cell and chlorophyll a, total carotene and observed yield when grown in inorganic media with sodium acetate. Total protein of S. gracile was higher than A. convolutus followed by C. vulgaris, whereas reverse trend was observed in the case of total lipid. Among 11 essential amino acids (EAAs), phenylalanine, leucine and lysine were found to be higher in C. vulgaris, S. gracile and A. convolutus than other EAAS. All the evaluated polyunsaturated fatty acids (PUFAs) of CIS, C20 and C22 were higher in C. vulgaris grown in Bold Basal Medium with sodium (Na) acetate (BBMAC) and Modified Medium with Na acetate (MMAC) than cultured in other media. In addition, S. gracile and A. convolutus grown in BBMAC and MMAC contained significantly (p<0.05) higher amount of PUFAs except linolenic acid ( 18:3n-3 ) and eicosatrienoic acid (20: 3n-6) than cultured in other media. All together 26 essential minerals were detected and 22 essential minerals were quantified where total bioaccumulated minerals was below the optimum level and significantly (p <0.01) correlated with these minerals available in media

Growth and nutritional value of a Tropical Green Alga, Ankistrodesmus convolutus corda, in Agro-industrialeffluents

Use of agro-industrial effluents for microalgal culture was investigated using a tropical freshwater green alga, Ankistrodesmus convolutus cultured in various dilutions of latex concentrate effluent (LCRE), standard Malaysian rubber effluent (SMRE) and digested palm oil mill effluent (POMED). Ankistrodesmus convolutus grown in 40%and 60%LCRE, 60%SMRE and 10% POMED showed significantly higher (P < 0.05) specific growth rate in terms of cell number and chlorophyll a than that grown in other effluent media and inorganic fertiliser (N:P:K = 1:1:0.5) as control. Total biomass of this microalgae grown in 60%LCRE, 60%SMRE and 10% POMED was significantly higher (P < 0.05) than that cultured in other effluent media and the control. Ankistrodesmus convolutus cultured in 40% and 60% LCRE, 60% SMRE and 10% POMED showed significantly (P < 0.05) higher amount of crude protein and lipid than that grown in other effluent media and the control. Significantly higher (P < 0.05) amount of most of the essential amino acids (EAAs) except a few were found in A. convolutus cultured in 60% LCRE and 60% SMRE than that grown in other effluent media and control. Ankistrodesmus convolutus cultured in 10% POMED resulted in significantly higher (P < 0.05) amount of all the EAAs except threonine and tyrosine that were grown in other POMED media and control. Ankistrodesmus convolutus grown in 40% and 60% LCRE, contained significantly higher (P < 0.05) amounts of all the C18 and C20 polyunsaturated fatty acids (PDFAs) than that cultured in other SMRE media and control, except eicosadienoic acid (20: 2n-11). A similar trend of PUFAs was recorded in A. convolutus cultured in 60% SMRE except eicosatrienoic acid (20:3n-6) and arachidonic acid (20:4n-6). It was found that A. convolutus contained significantly (P < 0.05) higher amount of PUFAs such as linoleic acid (l8:2n-6), linolenic acid (18:3n-3) and arachidonic acid (20:4n-6) when grown in 10% POMED than that cultured in other POMED media and control. This study showed that A. convolutus grown in 40-60% rubber and 10% POMED has higher nutritional value that that cultured in other effluent media and inogranic fertilizer

Studies on some Australian pottiaceous mosses

Chionoloma bombayense (Müll. Hal.) P. Sollm. [syn. Pseudosymblepharis bombayensis (Müll. Hal.) P. Sollm.] and Syntrichia serrata (Dixon) R.H. Zander are reported new for Australia. Barbula hampeana Paris is identical with Barbula hornschuchiana Schultz. Pottia tasmanica Broth. and Pottia brevicaulis (Taylor) Müll. Hal. are considered new synonyms of Microbryum starkeanum (Hedw.) R.H. Zander. Comments on a nomen nudum, Tortula brachytheca Burchard, are given

Sequence Analysis and Potentials of the Native RbcS Promoter in the Development of an Alternative Eukaryotic Expression System Using Green Microalga Ankistrodesmus convolutus

The availability of highly active homologous promoters is critical in the development of a transformation system and improvement of the transformation efficiency. To facilitate transformation of green microalga Ankistrodesmus convolutus which is considered as a potential candidate for many biotechnological applications, a highly-expressed native promoter sequence of ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (AcRbcS) has been used to drive the expression of β-glucuronidase (gusA) gene in this microalga. Besides the determination of the transcription start site by 5′-RACE, sequence analysis revealed that AcRbcS promoter contained consensus TATA-box and several putative cis-acting elements, including some representative light-regulatory elements (e.g., G-box, Sp1 motif and SORLIP2), which confer light responsiveness in plants, and several potential conserved motifs (e.g., CAGAC-motif, YCCYTGG-motifs and CACCACA-motif), which may be involved in light responsiveness of RbcS gene in green microalgae. Using AcRbcS promoter::gusA translational fusion, it was demonstrated that this promoter could function as a light-regulated promoter in transgenic A. convolutus, which suggested that the isolated AcRbcS promoter was a full and active promoter sequence that contained all cis-elements required for developmental and light-mediated control of gene expression, and this promoter can be used to drive the expression of heterologous genes in A. convolutus. This achievement therefore advances the development of A. convolutus as an alternative expression system for the production of recombinant proteins. This is the first report on development of gene manipulation system for unicellular green alga A. convolutus

Cloning and characterization of ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (RbcS) cDNA from green microalga Ankistrodesmus convolutus

An initial study on gene cloning and characterization of unicellular green microalga Ankistrodesmus convolutus was carried out to isolate and characterize the full-length cDNA of ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (RbcS) as a first step towards elucidating the structure of A. convolutus RbcS gene. The full-length of A. convolutus RbcS cDNA (AcRbcS) contained 28 bp of 5' untranslated region (UTR), 225 bp of 3' non-coding region, and an open reading frame of 165 amino acids consisting of a chloroplast transit peptide with 24 amino acids and a mature protein of 141 amino acids. The amino acid sequence has high identity to those of other green algae RbcS genes. The AcRbcS contained a few conserved domains including protein kinase C phosphorylation site, tyrosine kinase phosphorylation site and N-myristoylation sites. The AcRbcS was successfully expressed in Escherichia coli and a ~21 kDa of anticipated protein band was observed on SDS-PAGE. From the phylogenetic analysis of RbcS protein sequences, it was found that the RbcS of A. convolutus has closer genetic relationship with green microalgae species compared to those of green seaweed and green macroalgae species. Southern hybridization analysis revealed that the AcRbcS is a member of a small multigene family comprising of two to six members in A. convolutus genome. Under different illumination conditions, RT-PCR analysis showed that AcRbcS transcription was reduced in the dark, and drastically recovered in the light condition. Results presented in this paper established a good foundation for further study on the photosynthetic process of A. convolutus and other green algae species where little information is known on Rubisco small subunit

Siluro-Devonian graptolite stratigraphy of the Catalonian Coastal Ranges

Two facies characterize the Silurian and lower Devonian of the Catalonian Coastal Ranges, namely euxinic and pelagic carbonate facies. The first, is represented by black shales in which the atavus, acinaces, cyphus, triangulatus, convolutus, ?sedgwickii, ellesae and tumescens zones have been recognized. The graptolite succesion is far from complete on present evidence, but this is probably due to unfavorable environmental (taphonomic) conditions. This facies is similar to that prevailing throughout the Iberian massif and most of western Europe. The pelagic carbonate facies is peculiar to the Pridoli and lower Devonian and corresponds to the facies type prevailing in the Western Mediterranean Area. It is characterized by the nodular texture of limestones and marls, with all gradations between nodular limestones, marls and slates. Massive nodular limestone, occur in the lower partof the sequence (La Creu Formation) while the alternation of limestones, marls and slates charaterizes the upper part (Olorda Formation). Orthoconic cephalopds, crinoids, conodonts and tentaculites are the most common fossils present; graptolites occur in some shale horizons in the lower part of the Olorda Formation. These graptolites give strong indications of the uniformis and hercynicus zones (Lochkovian). The uppermost part of the sequence has not provided any graptolite fauna, but according their dacrioconarid fauna it corresponds probably to the Pragian

New distributional records of Mecoptera (Insecta) from Colombia

We present new distributional records for two Colombian species of Bittacidae. Pazius convolutus García-García &amp; Cadena-Castañeda, 2015 and Bittacus panamensis Byers, 1958 previously known from Cundinamarca department are herein newly recorded from Santander and Magdalena, respectively. In addition, we recorded Bittacus pignatelli Navás, 1932 in Colombia for the first time, increasing the number of species of Mecoptera in the country. Comments about mating behavior of P. convolutus, as well as a distribution map and a check-list of Colombian species of Mecoptera are included

Construction of cDNA library and preliminary analysis of expressed sequence tags from green microalga Ankistrodesmus convolutus Corda

Green microalga Ankistrodesmus convolutus Corda is a fast growing alga which produces appreciable amount of carotenoids and polyunsaturated fatty acids. To our knowledge, this is the first report on the construction of cDNA library and preliminary analysis of ESTs for this species. The titers of the primary and amplified cDNA libraries were 1.1×10(6) and 6.0×10(9) pfu/ml respectively. The percentage of recombinants was 97% in the primary library and a total of 337 out of 415 original cDNA clones selected randomly contained inserts ranging from 600 to 1,500 bps. A total of 201 individual ESTs with sizes ranging from 390 to 1,038 bps were then analyzed and the BLASTX score revealed that 35.8% of the sequences were classified as strong match, 38.3% as nominal and 25.9% as weak match. Among the ESTs with known putative function, 21.4% of them were found to be related to gene expression, 14.4% ESTs to photosynthesis, 10.9% ESTs to metabolism, 5.5% ESTs to miscellaneous, 2.0% to stress response, and the remaining 45.8% were classified as novel genes. Analysis of ESTs described in this paper can be an effective approach to isolate and characterize new genes from A. convolutus and thus the sequences obtained represented a significant contribution to the extensive database of sequences from green microalgae