scholarly journals Phytoplankton exudates and lysates support distinct microbial consortia with specialized metabolic and ecophysiological traits

2021 ◽  
Vol 118 (41) ◽  
pp. e2101178118
Author(s):  
Brandon Kieft ◽  
Zhou Li ◽  
Samuel Bryson ◽  
Robert L. Hettich ◽  
Chongle Pan ◽  
...  
Keyword(s):  
Carbon Assimilation ◽  
Stable Isotope Probing ◽  
Marine Phytoplankton ◽  
Microbial Consortia ◽  
Model Organisms ◽  
Ecophysiological Traits ◽  
Physiological Adaptations ◽  
Heterotrophic Microbes ◽  
Natural Microbial Community ◽  
The Relationship

Blooms of marine phytoplankton fix complex pools of dissolved organic matter (DOM) that are thought to be partitioned among hundreds of heterotrophic microbes at the base of the food web. While the relationship between microbial consumers and phytoplankton DOM is a key component of marine carbon cycling, microbial loop metabolism is largely understood from model organisms and substrates. Here, we took an untargeted approach to measure and analyze partitioning of four distinct phytoplankton-derived DOM pools among heterotrophic populations in a natural microbial community using a combination of ecogenomics, stable isotope probing (SIP), and proteomics. Each 13C-labeled exudate or lysate from a diatom or a picocyanobacterium was preferentially assimilated by different heterotrophic taxa with specialized metabolic and physiological adaptations. Bacteroidetes populations, with their unique high-molecular-weight transporters, were superior competitors for DOM derived from diatom cell lysis, rapidly increasing growth rates and ribosomal protein expression to produce new relatively high C:N biomass. Proteobacteria responses varied, with relatively low levels of assimilation by Gammaproteobacteria populations, while copiotrophic Alphaproteobacteria such as the Roseobacter clade, with their diverse array of ABC- and TRAP-type transporters to scavenge monomers and nitrogen-rich metabolites, accounted for nearly all cyanobacteria exudate assimilation and produced new relatively low C:N biomass. Carbon assimilation rates calculated from SIP data show that exudate and lysate from two common marine phytoplankton are being used by taxonomically distinct sets of heterotrophic populations with unique metabolic adaptations, providing a deeper mechanistic understanding of consumer succession and carbon use during marine bloom events.*

scholarly journals Experimental researches on vegetable assimilation and respiration. XVII.—The diurnal rhythm of assimilation in leaves of cherry laurel at “limiting” concentrations of carbon dioxide

1928 ◽  
Vol 102 (720) ◽  
pp. 467-487 ◽  
Keyword(s):  
Carbon Dioxide ◽  
General Relation ◽  
Carbon Assimilation ◽  
Simple Type ◽  
Green Cell ◽  
Water Plants ◽  
Experimental Researches ◽  
The Relationship ◽  
Direct Proportionality ◽  
Cherry Laurel

The primary general relation between external supply of carbon dioxide and rate of carbon assimilation in light by the green cells of plants has been investigated by many plant physiologists, and in general, so long as the assimilation is appreciably below the maxima permitted by the light intensity employed and by the temperature of the green cell, the relationship may be held to approximate to direct proportionality between rate of assimilation and external concentration (partial pressure) of CO 2 . The case seems most clear for water plants, where a direct proportionality has been demonstrated by Blackman and Smith, 1911 (2), for Elodea. The experiments of Brown and Escombe, 1902 (4), with land leaves, at concentrations of CO 2 up to seven times that of ordinary air, point in the same direction, and although the results of later workers with land leaves (Boysen-Jensen, 1918 (3), and Lundegardh, 1921 (7) ), do not in some other respects conform to the simple type shown by the Elodea results, yet, so far as the direct proportionality between CO 2 concentration and apparent assimilation is concerned, the position is rather strengthened than otherwise.

Zygnematophyceae: from living algae collections to the establishment of future models

2020 ◽  
Vol 71 (11) ◽  
pp. 3296-3304
Author(s):  
Hong Zhou ◽  
Klaus von Schwartzenberg
Keyword(s):  
Model Organism ◽  
Past Research ◽  
Model Organisms ◽  
Current Status ◽  
Future Research ◽  
Suitable Model ◽  
Research Perspectives ◽  
Robust Model ◽  
Physiological Adaptations ◽  
Long Time

Abstract The class of conjugating green algae, Zygnematophyceae (Conjugatophyceae), is extremely rich in species and has attracted the interest of phycologists for a long time. It is now widely accepted that this class of charophyte algae holds a key position in the phylogenetic tree of streptophytes, where they represent the closest relatives to all land plants (embryophytes). It is increasingly evident that robust model plants that can be easily cultivated and genetically transformed are necessary to better understand the process of terrestrialization and the related molecular, cellular, and physiological adaptations. Living algae collections play an important role, not only for phylogenomic-based taxonomy but also for screening for suitable model organisms. For this review, we screened six major public algae collections for Zygnematophyceae strains and established a cumulative list comprising 738 different taxa (including species, subspecies, varieties, and forms). From the described biodiversity with 8883 registered taxa (AlgaeBase) the cultured Zygnematophyceae taxa worldwide cover only ~8.3%. We review the past research on this clade of algae and discuss it from the perspective of establishing a model organism. We present data on the life cycle of the genera Micrasterias and Spirogyra, representing the orders Desmidiales and Zygnematales, and outline the current status of genetic transformation of Zygnematophyceae algae and future research perspectives.

scholarly journals Need for Laboratory Ecosystems To Unravel the Structures and Functions of Soil Microbial Communities Mediated by Chemistry

mBio ◽  
2018 ◽  
Vol 9 (4) ◽  
Author(s):  
Kateryna Zhalnina ◽  
Karsten Zengler ◽  
Dianne Newman ◽  
Trent R. Northen
Keyword(s):  
Microbial Communities ◽  
Metabolic Networks ◽  
Soil Microbial Communities ◽  
Microbial Interactions ◽  
Microbial Consortia ◽  
Cellular Biology ◽  
Model Organisms ◽  
Soil Microbial ◽  
Integrative Framework ◽  
Genome Annotations

ABSTRACTThe chemistry underpinning microbial interactions provides an integrative framework for linking the activities of individual microbes, microbial communities, plants, and their environments. Currently, we know very little about the functions of genes and metabolites within these communities because genome annotations and functions are derived from the minority of microbes that have been propagated in the laboratory. Yet the diversity, complexity, inaccessibility, and irreproducibility of native microbial consortia limit our ability to interpret chemical signaling and map metabolic networks. In this perspective, we contend that standardized laboratory ecosystems are needed to dissect the chemistry of soil microbiomes. We argue that dissemination and application of standardized laboratory ecosystems will be transformative for the field, much like how model organisms have played critical roles in advancing biochemistry and molecular and cellular biology. Community consensus on fabricated ecosystems (“EcoFABs”) along with protocols and data standards will integrate efforts and enable rapid improvements in our understanding of the biochemical ecology of microbial communities.

scholarly journals Evolution of the turtle bauplan: the topological relationship of the scapula relative to the ribcage

2012 ◽  
Vol 8 (6) ◽  
pp. 1028-1031 ◽  
Author(s):  
Tyler R. Lyson ◽  
Walter G. Joyce
Keyword(s):  
Shoulder Girdle ◽  
Developmental Model ◽  
Model Organisms ◽  
Turtle Shell ◽  
Developmental Origin ◽  
Topological Relationship ◽  
Fossil Data ◽  
Relationship Of ◽  
The Relationship

The turtle shell and the relationship of the shoulder girdle inside or ‘deep’ to the ribcage have puzzled neontologists and developmental biologists for more than a century. Recent developmental and fossil data indicate that the shoulder girdle indeed lies inside the shell, but anterior to the ribcage. Developmental biologists compare this orientation to that found in the model organisms mice and chickens, whose scapula lies laterally on top of the ribcage. We analyse the topological relationship of the shoulder girdle relative to the ribcage within a broader phylogenetic context and determine that the condition found in turtles is also found in amphibians, monotreme mammals and lepidosaurs. A vertical scapula anterior to the thoracic ribcage is therefore inferred to be the basal amniote condition and indicates that the condition found in therian mammals and archosaurs (which includes both developmental model organisms: chickens and mice) is derived and not appropriate for studying the developmental origin of the turtle shell. Instead, among amniotes, either monotreme mammals or lepidosaurs should be used.

Mechanisms of Tri-N-Butyltin Bioaccumulation by Marine Phytoplankton

1989 ◽  
Vol 46 (5) ◽  
pp. 859-862 ◽  
Author(s):  
Thomas C. Chiles ◽  
Peter D. Pendoley ◽  
Roy B. Laughlin Jr.
Keyword(s):  
Linear Relationship ◽  
Isochrysis Galbana ◽  
Competitive Binding ◽  
Marine Microalgae ◽  
Marine Phytoplankton ◽  
Chaetoceros Gracilis ◽  
Synechococcus Sp ◽  
The Relationship ◽  
Fold Excess

We examined uptake of tri-n-butyltin (TBT) by three genera of marine microalgae and one genus of cyanobacterium. There was a linear relationship between external concentrations of TBT and cell burdens in the microalgae Nannochloris sp., Chaetoceros gracilis, and the cyanobacterium Synechococcus sp. (PR-6). The relationship between external TBT concentrations and cell TBT burdens was distinctly nonlinear for Isochrysis galbana. Competitive binding experiments showed a decrease of approximately 88% of the total bound radiolabeled TBT to I. galbana in the presence of a 200-fold excess of unlabeled TBT. No significant decrease of bound TBT was observed for Nannochloris sp. These studies demonstrate that either partitioning or binding may control bioaccumulation of TBT by marine phytoplankton.

scholarly journals Bacterial physiological adaptations to contrasting edaphic conditions identified using landscape scale metagenomics

2017 ◽  
Author(s):  
Ashish A. Malik ◽  
Bruce C. Thomson ◽  
Andrew S. Whiteley ◽  
Mark Bailey ◽  
Robert I. Griffiths
Keyword(s):  
Alpha Diversity ◽  
Gamma Diversity ◽  
Organic C ◽  
Edaphic Conditions ◽  
Acquisition Strategies ◽  
Physiological Adaptations ◽  
Geographically Distributed ◽  
C And N ◽  
Functional Profiles ◽  
The Relationship

AbstractEnvironmental factors relating to soil pH are widely known to be important in structuring soil bacterial communities, yet the relationship between taxonomic community composition and functional diversity remains to be determined. Here, we analyze geographically distributed soils spanning a wide pH gradient and assess the functional gene capacity within those communities using whole genome metagenomics. Low pH soils consistently had fewer taxa (lower alpha and gamma diversity), but only marginal reductions in functional alpha diversity and equivalent functional gamma diversity. However, coherent changes in the relative abundances of annotated genes between pH classes were identified; with functional profiles clustering according to pH independent of geography. Differences in gene abundances were found to reflect survival and nutrient acquisition strategies, with organic-rich acidic soils harboring a greater abundance of cation efflux pumps, C and N direct fixation systems and fermentation pathways indicative of anaerobiosis. Conversely, high pH soils possessed more direct transporter-mediated mechanisms for organic C and N substrate acquisition. These findings show that bacterial functional versatility may not be constrained by taxonomy, and we further identify the range of physiological adaptations required to exist in soils of varying nutrient availability and edaphic conditions.

scholarly journals Surviving Starvation: Proteomic and Lipidomic Profiling of Nutrient Deprivation in the Smallest Known Free-Living Eukaryote

Metabolites ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 273
Author(s):  
Sarah F. Martin ◽  
Mary K. Doherty ◽  
Eliane Salvo-Chirnside ◽  
Seshu R. Tammireddy ◽  
Jiaxiuyu Liu ◽  
...  
Keyword(s):  
Model Organism ◽  
Carbon Assimilation ◽  
Phospholipid Metabolism ◽  
Marine Phytoplankton ◽  
Nitrogen And Phosphorus ◽  
Free Living ◽  
Betaine Lipids ◽  
Low Phosphorus ◽  
Adaptive Processes ◽  
Low Levels

Marine phytoplankton, comprising cyanobacteria, micro- and pico-algae are key to photosynthesis, oxygen production and carbon assimilation on Earth. The unicellular green picoalga Ostreococcus tauri holds a key position at the base of the green lineage of plants, which makes it an interesting model organism. O. tauri has adapted to survive in low levels of nitrogen and phosphorus in the open ocean and also during rapid changes in the levels of these nutrients in coastal waters. In this study, we have employed untargeted proteomic and lipidomic strategies to investigate the molecular responses of O. tauri to low-nitrogen and low-phosphorus environments. In the absence of external nitrogen, there was an elevation in the expression of ammonia and urea transporter proteins together with an accumulation of triglycerides. In phosphate-limiting conditions, the expression levels of phosphokinases and phosphate transporters were increased, indicating an attempt to maximise scavenging opportunities as opposed to energy conservation conditions. The production of betaine lipids was also elevated, highlighting a shift away from phospholipid metabolism. This finding was supported by the putative identification of betaine synthase in O. tauri. This work offers additional perspectives on the complex strategies that underpin the adaptive processes of the smallest known free-living eukaryote to alterations in environmental conditions.

Sign in / Sign up

Export Citation Format

Share Document