Olga Sánchez

Olga Sánchez
Autonomous University of Barcelona | UAB · Department of Genetics and Microbiology

About

72
Publications
11,642
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,927
Citations
Introduction
I am a microbial ecologist interested in understanding the diversity and function of microbial communities in natural or engineered systems, such as marine environments or wastewater treatment systems. In 2007 I became associate professor at the Department of Genetics and Microbiology of the Universitat Autònoma de Barcelona and currently, I collaborate with researchers from the Department of Marine Biology and Oceanography in the Institute of Marine Sciences in Barcelona combining conventional isolation techniques in culture media with -omics methods (genomics, transcriptomics) for the study of microorganisms from the ocean.

Publications

Publications (72)
Article
Full-text available
Microbial reduction of inorganic divalent mercury (Hg2+) and methylmercury (MeHg) demethylation is performed by the mer operon, specifically by merA and merB genes, respectively, but little is known about the mercury tolerance capacity of marine microorganisms and its prevalence in the ocean. Here, combining culture-dependent analyses with metageno...
Article
Full-text available
Estimation of prokaryotic growth rates is critical to understand the ecological role and contribution of different microbes to marine biogeochemical cycles. However, there is a general lack of knowledge on what factors control the growth rates of different prokaryotic groups and how these vary between sites and along seasons at a given site. We car...
Article
Biological wastewater treatment processes are based on the exploitation of the concerted activity of microorganisms. Knowledge on the microbial community structure and the links to the changing environmental conditions is therefore crucial for the development and optimization of biological systems by engineers. The advent of molecular techniques oc...
Article
The aerobic anoxygenic phototrophic (AAP) bacteria are common in most marine environments but their global diversity and biogeography remain poorly characterized. Here, we analyzed AAP communities across 113 globally-distributed surface ocean stations sampled during the Malaspina Expedition in the tropical and subtropical ocean. By means of amplico...
Article
Two strains isolated from a sample of activated sludge that was obtained from a seawater-based wastewater treatment plant on the southeastern Mediterranean coast of Spain have been characterized to achieve their taxonomic classification, since preliminary data suggested they could represent novel taxa. Given the uniqueness of this habitat, as this...
Article
Full-text available
Cork matrices biofunctionalized with Moringa oleifera seed extracts (MoSe) have potential for use as a biofilter with antibacterial properties to reduce waterborne pathogens. The aim of this study was to evaluate the effect of cork biofunctionalized with active antimicrobial compounds of MoSe (f-cork) on the inhibition of Escherichia coli (InhEc)....
Preprint
Full-text available
Microbial reduction of inorganic divalent mercury (Hg ²⁺ ) and methylmercury (MeHg) demethylation is performed by the mer operon, specifically by merA and merB genes respectively, but little is known about the mercury tolerance capacity of marine microorganisms and its prevalence in the global ocean. Here, we explored the distribution of these gene...
Article
Full-text available
Background: Isolation of marine microorganisms is fundamental to gather information about their physiology, ecology and genomic content. To date, most of the bacterial isolation efforts have focused on the photic ocean leaving the deep ocean less explored. We have created a marine culture collection of heterotrophic bacteria (MARINHET) using a sta...
Article
Strain ISS653T, isolated from Atlantic seawater, is a yellow pigmented, non-motile, Gram-reaction-negative rod-shaped bacterium, strictly aerobic and chemoorganotrophic, slightly halophilic (1-15 % NaCl) and mesophilic (4-37 °C), oxidase- and catalase-positive and proteolytic. Its major cellular fatty acids are iso-C15 : 0, iso-C15 : 0 2-OH, and is...
Preprint
Full-text available
Background: Isolation of marine microorganisms is fundamental to gather information about their physiology, ecology and genomic content. To date, most of the bacterial isolation efforts have focused on the photic ocean leaving the deep ocean less explored. We have created a marine culture collection of heterotrophic bacteria (MARINHET) using a stan...
Preprint
Full-text available
Nowadays, there is a significant gap in the knowledge of the diversity and patterns for marine heterotrophic culturable microorganisms. In addition, most of the bacterial isolation efforts have focused on the photic ocean leaving the deep ocean less explored. We have isolated 1561 bacterial strains covering both photic (817) and aphotic layers (744...
Article
Full-text available
We studied the long-term temporal dynamics of the aerobic anoxygenic phototrophic (AAP) bacteria, a relevant functional group in the coastal marine microbial food web, using high-throughput sequencing of the pufM gene coupled with multivariate, time series and co-occurrence analyses at the Blanes Bay Microbial Observatory (NW Mediterranean). Additi...
Article
Agricultural practices have raised the level of nutrients reaching aquifers. In Europe, nitrate pollution is considered as one of the main threats for the quality of groundwater in agricultural areas. Treatment wetlands (TWs), also known as Constructed Wetlands, are used for groundwater treatment in areas with an important concentration of nitrogen...
Article
The main goal of the present study was to enhance the rhizobacterium potential in a horizontal subsurface flow constructed wetland system planted with Phragmites australis, through environmentally friendly biological approaches. The bioinoculation of antagonist bacteria has been used to promote higher rhizosphere competence and improve pathogenic b...
Chapter
Full-text available
The microbial community of seven different small‐scale constructed wetlands (CWs) treating urban wastewater was analyzed to establish possible relationships between microbial richness and pollutant removal [organic matter, nutrients and pharmaceuticals and personal care products (PPCPs)], and between microbial richness and physico‐chemical paramete...
Preprint
Full-text available
Aerobic anoxygenic phototrophic (AAP) bacteria play a relevant role in the marine microbial food web, but little is known about their long-term seasonal dynamics. Using Illumina amplicon sequencing of the puf M gene coupled with multivariate, time series and co-occurrence analyses we examined their temporal dynamics over a decade at the Blanes Bay...
Article
Biofilm occurrence in reverse osmosis (RO) membranes constitutes a key problem in water plants, leading to a loss of performance and a decrease in treatment efficiency. Knowledge on the microbial community composition and the links to operational conditions is therefore crucial to understand biofilm formation and develop proper biofouling managemen...
Article
Aerobic anoxygenic phototrophic (AAP) bacteria are microorganisms that can harvest light energy using bacteriochlorophyll a to supplement their predominantly organotrophic metabolism. Growth enhancement by light has repeatedly been demonstrated in laboratory experiments with AAP isolates. However, the ecological advantage of light utilization is un...
Article
Full-text available
Constructed wetlands (CWs) constitute an interesting alternative option to conventional systems for wastewater treatment. This technology is based on the utilization of the concerted activity of microorganisms for the removal of contaminants. Consequently, knowledge on the microbial assemblages dwelling CWs and the different environmental factors w...
Article
Estimation of growth rates is crucial to understand the ecological role of prokaryotes and their contribution to marine biogeochemical cycling. However, there are only a few estimates for individual taxa. Two top-down (grazing) and bottom-up (phosphorus (P) availability) manipulation experiments were conducted under different light regimes in the N...
Article
Full-text available
The diversity of the bacterial community developed in different stages of two reverse osmosis (RO) water reclamation demonstration plants designed in a wastewater treatment plant (WWTP) in Tarragona (Spain) was characterized by applying 454-pyrosequencing of the 16S rRNA gene. The plants were fed by secondary treated effluent to a conventional pret...
Chapter
Constructed wetlands are becoming an interesting alternative for wastewater reuse since high concentrations of contaminants and pathogenic microorganisms can be removed with these natural treatment systems. In this study, experimental constructed wetlands treating diluted wastewater were used to study the effect of plant species (Typha angustifolia...
Chapter
The traditional scarcity of hydric resources in Spain linked with a growing trend in water demand for applications such as landscaping, gardening or agricultural irrigation is gradually shifting water management practices towards the use of reclaimed water obtained from wastewater treatment plants. From a sustainable point of view, reclaimed water...
Article
The prokaryotic microbial communities (Bacteria and Archaea) of three different systems operating in Denmark for the treatment of domestic wastewater (horizontal flow constructed wetlands (HFCW), vertical flow constructed wetlands (VFCW) and biofilters (BF)) was analysed using endpoint PCR followed by Denaturing Gradient Gel Electrophoresis (DGGE)....
Article
Full-text available
Drip irrigation systems using reclaimed water often present clogging events of biological origin. Microbial communities in biofilms from microirrigation systems of an experimental greenhouse in Almería, SE Spain, which used two different qualities of water (treated wastewater and reclaimed water), were analyzed by denaturing gradient gel electropho...
Article
Full-text available
The bacterial community composition of activated sludge from a wastewater treatment plant (Almería, Spain) with the particularity of using seawater was investigated by applying 454-pyrosequencing. The results showed that Deinococcus-Thermus, Proteobacteria, Chloroflexi and Bacteroidetes were the most abundant retrieved sequences, while other groups...
Data
Genera identified from pyrosequencing and cloning in the saline activated sludge.
Data
Summary of clean sequences, singletons and operational taxonomic units (OTUs) in the two data sets analysed.
Data
Dendrogram resulting from hierarchical clustering (A) and non-metrical multidimensional (NMDS) plot (B) based on Bray–Curtis dissimilarities between biofilm samples calculated from the square root transformed relative abundance of each band from the DGGE fingerprint. In the NMDS plot, samples derived from SEW are represented in black and those from...
Data
Taxonomic composition by phylum and class for the sequences retrieved in 2 consecutive years.
Data
Percentage of relative intensity of DGGE bands, clones (library), probe positive cells scaled to Eub probes (FISH) and reads (454) affiliated to different phylogenetic groups from samples D07 and D08. Data from DGGE, cloning and FISH have been extracted from Sánchez and colleagues (2011). [Alphaproteobacteria (Alpha), Betaproteobacteria (Beta), Gam...
Article
We present measurements of glucose, amino acids, and adenosine triphosphate (ATP) bacterial uptake at tracer concentrations across an oceanic gradient from the Cape Blanc upwelling to the Northeast Atlantic subtropical gyre. The bulk uptake of the compounds increased in the upwelling, with amino acids being the most actively taken up substrate (up...
Article
Current output of microbial fuel cells (MFCs) depends on a number of engineering variables mainly related to the design of the fuel cell reactor and the materials used. In most cases the engineering of MFCs relies on the premise that for a constant biomass, current output correlates well with the metabolic activity of the cells. In this study we an...
Article
A photo-Fenton-membrane bioreactor (MBR) coupled system is an innovative tool for the treatment of wastewater containing high quantities of contaminants. In this paper, wastewater with 200 mg l(-1) of dissolved organic carbon (DOC) of a selected mixture of five commercial pesticides: Vydate®, Metomur®, Couraze®, Ditimur-40®, and Scala® was treated...
Article
The prokaryotic community composition of activated sludge from a seawater-processing wastewater treatment plant (Almeria, Spain) was investigated by using the rRNA approach, combining different molecular techniques such as denaturing gradient gel electrophoresis (DGGE), clone libraries and in situ hybridization (FISH and CARD-FISH). Most of the seq...
Article
Microbial activity can be measured using sensors based on microbial fuel cell technology. In these sensors, the strength and stability of the signal depend among others on the type of catalyst used at the cathode since different power outputs can be reached depending on the catalyst. For this reason, it is necessary to know the efficiency of differ...
Article
Full-text available
Phototrophic biofilms are used in a variety of biotechnological and industrial processes. Understanding their structure, ie microbial composition, is a necessary step for understanding their function and, ultimately, for the success of their application. DNA analysis methods can be used to obtain information on the taxonomic composition and relativ...
Article
Although SAR11 is usually the dominant bacterial group in most marine ecosystems when analyzed with clone libraries and fluorescence in situ hybridization, it is often not retrieved in studies where denaturing gradient gel electrophoresis (DGGE) has been used. We analyzed the microdiversity of SAR11 in Blanes Bay (NW Mediterranean) and we suggest t...
Chapter
Microbial mats consist of multi-layered microbial communities organized in space as a result of steep physicochemical gradients. They can be found in sheltered and shallow coastal areas and intertidal zones where they flourish whenever extreme temperatures, dryness or saltiness act to exclude plants and animals. Several metabolically active microor...
Article
Full-text available
Analysis of marine cyanobacteria and proteobacteria genomes has provided a profound understanding of the life strategies of these organisms and their ecotype differentiation and metabolisms. However, a comparable analysis of the Bacteroidetes, the third major bacterioplankton group, is still lacking. In the present paper, we report on the genome of...
Article
We collected surface samples in Franklin Bay (Western Arctic) from ice-covered to ice-free conditions, to determine seasonal changes in the identity and in situ activity of the prokaryotic assemblages. Catalysed reported fluorescence in situ hybridization was used to quantify the abundance of different groups, and combined with microautoradiography...
Article
Full-text available
This work describes the effect of several parameters that affect the operation of a microbial fuel cell (MFC). It is based on a methodology employed in previous studies which use Escherichia coli as biocatalyst and neutral red as the electron mediator in what is called a mediated electron transfer (MET) microbial fuel cell. The influence of the bac...
Chapter
Full-text available
Laboratory cultures have been extensively used in the past as a tool to study the behavior of model organisms subject to a variety of environmental conditions and hence to extrapolate the type of behavior that could be expected from similar microorganisms living in nature. The information obtained using this approach has been crucial for our curren...
Article
An annual seasonal cycle of composition of a bacterioplankton community in an oligotrophic coastal system was studied by denaturing gradient gel electrophoresis (DGGE) using five different primer sets. Analysis of DGGE fingerprints showed that primer set 357fGC-907rM grouped samples according to seasons. Additionally, we used the set of 16S rRNA ge...
Article
We combined denaturing gradient gel electrophoresis (DGGE), catalysed reporter deposition-FISH (CARD-FISH) and clone libraries to investigate the seasonality of the bacterial assemblage composition in north-west Mediterranean coastal waters. DGGE analysis indicated that bacterial diversity changed gradually throughout the year, although with a clea...
Article
Full-text available
The potential of microbial mats to develop sulfide-oxidizing biofims was explored. A bioreactor specially designed for the treatment of sulfide-containing effluents was inoculated with a microbial-mat sample, and a complex microbial biofilm with sulfide-oxidation activity developed. The microbial composition of the biofilm was studied by pigment, m...
Chapter
Full-text available
Due to the deficiency hydric sources prevailing in many places all over the world, the use of treated waste water for irrigation or recharge is progressively becoming commonplace. The treatment of waste water prior to irrigation does not completely eliminated the existence of microbial contaminants and, therefore plants, soil and even aquifers may...
Article
Microbial consumption is one of the main processes, along with photolysis and ventilation, that remove the biogenic trace gas dimethylsulfide (DMS) from the surface ocean. Although a few isolates of marine bacteria have been studied for their ability to utilize DMS, little is known about the characteristics or phylogenetic affiliation of DMS consum...
Article
There is evidence that microbial mats are able to degrade petroleum components in polluted environments, but it is still a matter of discussion whether cyanobacteria from these mats participate actively in hydrocarbon biodegradation. In this work, we attempt to evaluate whether cyanobacteria can grow using crude oil as the sole carbon source. We us...
Article
Full-text available
Hydrocarbon-degrading microorganisms from natural environments have been isolated and identified using culture-dependent or molecular techniques. However, there has been little research into the occurrence of microorganisms incorporated into crude oil in the initial steps of extraction and handling, which can reduce the quality of stored petroleum....
Article
Full-text available
Recent studies have shown that the cyanobacterium Microcoleus chthonoplastes forms a consortium with heterotrophic bacteria present within the cyanobacterial sheath. These studies also show that this consortium is able to grow in the presence of crude oil, degrading aliphatic heterocyclic organo-sulfur compounds as well as alkylated monocyclic and...
Article
Full-text available
The diversity of a crude oil sample from the Tarragona basin (NE Spain) was assessed in order to determine the occurrence of potential hydrocarbon degraders able to grow in the absence of external electron acceptors. The experiments have been performed using an anaerobic bench-scale biofilm reactor. The taxonomic composition of the biofilm develope...
Article
Full-text available
This paper describes an illuminated reactor that allows the spontaneous development of biofilms aimed at the treatment of sulfide-containing streams. The reactor operates as a sulfidostat and is composed of an illuminated packed-column, in which microorganisms are exposed to constant low substrate concentrations, thereby avoiding inhibition due to...
Article
Full-text available
In the present work, we describe for the first time the utilization of a complex microbial biofilm for the treatment of sulfide-containing effluents. A non-aerated packed-column reactor was inoculated with anoxic lake sediment and exposed to light. A biofilm developed in the column and showed a stable oxidation performance for several weeks. Microb...
Article
Full-text available
Adenosine-5'-phosphosulfate (APS) reductase participates in the oxidation of sulfite to APS in Allochromatium vinosum. Oxidation of sulfite via the APS pathway yields ATP through substrate-level phosphorylation. An alternative enzyme for the oxidation of sulfite to sulfate, sulfite:acceptor oxidoreductase, has also been reported in Ach. vinosum. Ox...
Article
This article analyzes how absorption of light by suspensions of phototrophic bacteria is modulated by changes in the biomass of the culture, the size of the culture vessel and by the presence of refractile structures within the cells. Increases in biomass and culture size result in higher rates of light absorption but in the decrease of the amount...
Article
Continuous cultures of Chromatium vinosum DSM 185 were shifted from a high to a low irradiance (67 to 4 microE m(-2) s(-1)) and vice versa (4 to 67 microE m(-2) s(-1)). The kinetics of photoacclimation of the cultures were analysed during these transitions until steady state was reached. When irradiance was shifted from 4 to 67 microE m(-2) s(-1),...
Article
The photosynthetic response of the purple sulfur bacterium Chromatium vinosum DSM 185 to different degrees of illumination was analyzed. The microorganism was grown in continuous culture, and samples were taken from the effluent of the culture and incubated at different irradiances to determine the specific rate of sulfur oxidation as a measure of...
Article
This study describes how the phototrophic organism Chromatium vinosum, when grown under different degrees of light limitation, distributes the reducing power initially present in the medium as hydrogen sulfide. Under all the conditions of illumination tested, sulfur was the major store of reducing power. Glycogen, which was virtually absent under l...
Article
This paper describes a novel type of continuous culture for the growth of phototrophic sulfur oxidizers under constant concentrations of hydrogen sulfide. The culture maintains a constant concentration of sulfide despite possible variations in external factors likely to affect photosynthetic activity. Variations in biological activity lead to small...
Article
This article describes a novel method for the measurement of light absorption by cultures of phototrophic microorganisms. The rate of light absorption is calculated as the difference between the rate of light output from a culture containing cells and the rate of light output from a culture containing only growth medium. The specific rate of light...

Network

Cited By