scholarly journals The Antisense RNA Approach: a New Application forIn VivoInvestigation of the Stress Response of Oenococcus oeni, a Wine-Associated Lactic Acid Bacterium

2015 ◽  
Vol 82 (1) ◽  
pp. 18-26 ◽  
Author(s):  
Maud Darsonval ◽  
Tarek Msadek ◽  
Hervé Alexandre ◽  
Cosette Grandvalet
Keyword(s):  
Gene Expression ◽  
Lactic Acid ◽  
Stress Response ◽  
Lactic Acid Bacterium ◽  
Antisense Rna ◽  
Expression Vector ◽  
Stress Proteins ◽  
Oenococcus Oeni ◽  
Content Type

ABSTRACTOenococcus oeniis a wine-associated lactic acid bacterium mostly responsible for malolactic fermentation in wine. In wine,O. oenigrows in an environment hostile to bacterial growth (low pH, low temperature, and ethanol) that induces stress response mechanisms. To survive,O. oeniis known to set up transitional stress response mechanisms through the synthesis of heat stress proteins (HSPs) encoded by thehspgenes, notably a unique small HSP named Lo18. Despite the availability of the genome sequence, characterization ofO. oenigenes is limited, and little is known about thein vivorole of Lo18. Due to the lack of genetic tools forO. oeni, an efficient expression vector inO. oeniis still lacking, and deletion or inactivation of thehsp18gene is not presently practicable. As an alternative approach, with the goal of understanding the biological function of theO. oenihsp18genein vivo, we have developed an expression vector to produce antisense RNA targeting ofhsp18mRNA. Recombinant strains were exposed to multiple stresses inducinghsp18gene expression: heat shock and acid shock. We showed that antisense attenuation ofhsp18affectsO. oenisurvival under stress conditions. These results confirm the involvement of Lo18 in heat and acid tolerance ofO. oeni. Results of anisotropy experiments also confirm a membrane-protective role for Lo18, as previous observations had already suggested. This study describes a new, efficient tool to demonstrate the use of antisense technology for modulating gene expression inO. oeni.

scholarly journals Analysis of Transcriptomic Response to SO 2 by Oenococcus oeni Growing in Continuous Culture

2021 ◽  
Author(s):  
Cristobal A. Onetto ◽  
Peter J. Costello ◽  
Radka Kolouchova ◽  
Charlotte Jordans ◽  
Jane McCarthy ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacterium ◽  
High Sensitivity ◽  
Malolactic Fermentation ◽  
Oenococcus Oeni ◽  
Low Ph ◽  
Transcriptomic Response ◽  
Content Type ◽  
Bacterium Species ◽  
High Ethanol

Malolactic fermentation is an indispensable step in the elaboration of most wines and is generally performed by Oenococcus oeni , a Gram-positive heterofermentative lactic acid bacterium species. While O. oeni is tolerant to many of the wine stresses, including low pH and high ethanol concentrations, it has high sensitivity to SO 2 , an antiseptic and antioxidant compound regularly used in winemaking.

scholarly journals Distribution and Functions of Phosphotransferase System Genes in the Genome of the Lactic Acid Bacterium Oenococcus oeni

2013 ◽  
Vol 79 (11) ◽  
pp. 3371-3379 ◽  
Author(s):  
Zohra Jamal ◽  
Cécile Miot-Sertier ◽  
François Thibau ◽  
Lucie Dutilh ◽  
Aline Lonvaud-Funel ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacterium ◽  
Oenococcus Oeni ◽  
Phosphotransferase System ◽  
Content Type ◽  
Low Concentrations ◽  
Perfect Adaptation ◽  
Form Part ◽  
Genes Encoding ◽  
Enzyme I

ABSTRACTOenococcus oeni, the lactic acid bacterium primarily responsible for malolactic fermentation in wine, is able to grow on a large variety of carbohydrates, but the pathways by which substrates are transported and phosphorylated in this species have been poorly studied. We show that the genes encoding the general phosphotransferase proteins, enzyme I (EI) and histidine protein (HPr), as well as 21 permease genes (3 isolated ones and 18 clustered into 6 distinct loci), are highly conserved among the strains studied and may form part of theO. oenicore genome. Additional permease genes differentiate the strains and may have been acquired or lost by horizontal gene transfer events. The coreptsgenes are expressed, and permease gene expression is modulated by the nature of the bacterial growth substrate. DecryptifiedO. oenicells are able to phosphorylate glucose, cellobiose, trehalose, and mannose at the expense of phosphoenolpyruvate. These substrates are present at low concentrations in wine at the end of alcoholic fermentation. The phosphotransferase system (PTS) may contribute to the perfect adaptation ofO. oenito its singular ecological niche.

scholarly journals Lysogeny in the Lactic Acid Bacterium Oenococcus oeni Is Responsible for Modified Colony Morphology on Red Grape Juice Agar

2019 ◽  
Vol 85 (19) ◽  
Author(s):  
Amel Chaïb ◽  
Cécile Philippe ◽  
Féty Jaomanjaka ◽  
Olivier Claisse ◽  
Mickaël Jourdes ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacterium ◽  
Grape Juice ◽  
Oenococcus Oeni ◽  
Polyphenolic Compounds ◽  
Phenotypic Traits ◽  
Content Type ◽  
Red Color ◽  
Red Grape Juice ◽  
Red Grape

ABSTRACT Oenococcus oeni is the lactic acid bacterium (LAB) that most commonly drives malolactic fermentation in wine. Although oenococcal prophages are highly prevalent, their implications on bacterial fitness have remained unexplored and more research is required in this field. An important step toward achieving this goal is the ability to produce isogenic pairs of strains that differ only by the lysogenic presence of a given prophage, allowing further comparisons of different phenotypic traits. A novel protocol for the rapid isolation of lysogens is presented. Bacteria were first picked from the center of turbid plaques produced by temperate oenophages on a sensitive nonlysogenic host. When streaked onto an agar medium containing red grape juice (RGJ), cells segregated into white and red colonies. PCR amplifications with phage-specific primers demonstrated that only lysogens underwent white-red morphotypic switching. The method proved successful for various oenophages irrespective of their genomic content and attachment site used for site-specific recombination in the bacterial chromosome. The color switch was also observed when a sensitive nonlysogenic strain was infected with an exogenously provided lytic phage, suggesting that intracolonial lysis triggers the change. Last, lysogens also produced red colonies on white grape juice agar supplemented with polyphenolic compounds. We posit that spontaneous prophage excision produces cell lysis events in lysogenic colonies growing on RGJ agar, which, in turn, foster interactions between lysed materials and polyphenolic compounds to yield colonies easily distinguishable by their red color. Furthermore, the technique was used successfully with other species of LAB. IMPORTANCE The presence of white and red colonies on red grape juice (RGJ) agar during enumeration of Oenococcus oeni in wine samples is frequently observed by stakeholders in the wine industry. Our study brings an explanation for this intriguing phenomenon and establishes a link between the white-red color switch and the lysogenic state of O. oeni. It also provides a simple and inexpensive method to distinguish between lysogenic and nonlysogenic derivatives in O. oeni with a minimum of expended time and effort. Noteworthy, the protocol could be adapted to two other species of LAB, namely, Leuconostoc citreum and Lactobacillus plantarum. It could be an effective tool to provide genetic, ecological, and functional insights into lysogeny and aid in improving biotechnological processes involving members of the lactic acid bacterium (LAB) family.

scholarly journals Divergent Targets of Candida albicans Biofilm Regulator Bcr1In VitroandIn Vivo

2012 ◽  
Vol 11 (7) ◽  
pp. 896-904 ◽  
Author(s):  
Saranna Fanning ◽  
Wenjie Xu ◽  
Norma Solis ◽  
Carol A. Woolford ◽  
Scott G. Filler ◽  
...  
Keyword(s):  
Gene Expression ◽  
Candida Albicans ◽  
Stress Response ◽  
Growth Conditions ◽  
Gene Expression Measurement ◽  
Content Type ◽  
New Genes

ABSTRACTCandida albicansis a causative agent of oropharyngeal candidiasis (OPC), a biofilm-like infection of the oral mucosa. Biofilm formation depends upon theC. albicanstranscription factor Bcr1, and previous studies indicate that Bcr1 is required for OPC in a mouse model of infection. Here we have used a nanoString gene expression measurement platform to elucidate the role of Bcr1 in OPC-related gene expression. We chose for assays a panel of 134 genes that represent a range of morphogenetic and cell cycle functions as well as environmental and stress response pathways. We assayed gene expression in whole infected tongue samples. The results sketch a portrait ofC. albicansgene expression in which numerous stress response pathways are activated during OPC. This one set of experiments identifies 64 new genes with significantly altered RNA levels during OPC, thus increasing substantially the number of known genes in this expression class. Thebcr1Δ/Δ mutant had a much more limited gene expression defect during OPC infection than previously reported forin vitrogrowth conditions. Among major functional Bcr1 targets, we observed thatALS3was Bcr1 dependentin vivowhileHWP1was not. We used null mutants and complemented strains to verify that Bcr1 and Hwp1 are required for OPC infection in this model. The role of Als3 is transient and mild, though significant. Our findings suggest that the versatility ofC. albicansas a pathogen may reflect its ability to persist in the face of multiple stresses and underscore that transcriptional circuitry during infection may be distinct from that detailed duringin vitrogrowth.

scholarly journals Characterization of Host Responses duringPseudomonas aeruginosaAcute Infection in the Lungs and Blood and after Treatment with the Synthetic Immunomodulatory Peptide IDR-1002

2018 ◽  
Vol 87 (1) ◽  
Author(s):  
Kelli Wuerth ◽  
Amy H. Y. Lee ◽  
Reza Falsafi ◽  
Erin E. Gill ◽  
Robert E. W. Hancock
Keyword(s):  
Gene Expression ◽  
Bacterial Resistance ◽  
Lymphocyte Activation ◽  
Lavage Fluid ◽  
Innate Immune ◽  
Microbial Infection ◽  
Content Type ◽  
Innate Defense ◽  
Lung Infections

ABSTRACTPseudomonas aeruginosais an opportunistic pathogen that causes nosocomial pneumonia and infects patients with cystic fibrosis.P. aeruginosalung infections are difficult to treat due to bacterial resistance to antibiotics, and strains with multidrug resistance are becoming more prevalent. Here, we examined the use of a small host defense peptide, innate defense regulator 1002 (IDR-1002), in an acuteP. aeruginosalung infectionin vivo. IDR-1002 significantly reduced the bacterial burden in bronchoalveolar lavage fluid (BALF), as well as MCP-1 in BALF and serum, KC in serum, and interleukin 6 (IL-6) in BALF. Transcriptome sequencing (RNA-Seq) was conducted on lungs and whole blood, and the effects ofP. aeruginosa, IDR-1002, and the combination ofP. aeruginosaand IDR-1002 were evaluated. Differential gene expression analysis showed thatP. aeruginosaincreased multiple inflammatory and innate immune pathways, as well as affected hemostasis, matrix metalloproteinases, collagen biosynthesis, and various metabolism pathways in the lungs and/or blood. Infected mice treated with IDR-1002 had significant changes in gene expression compared to untreated infected mice, with fewer differentially expressed genes associated with the inflammatory and innate immune responses to microbial infection, and treatment also affected morphogenesis, certain metabolic pathways, and lymphocyte activation. Overall, these results showed that IDR-1002 was effective in treatingP. aeruginosaacute lung infections and associated inflammation.

scholarly journals Draft Genome Sequence of Enterococcus faecalis DD14, a Bacteriocinogenic Lactic Acid Bacterium with Anti-Clostridium Activity

2017 ◽  
Vol 5 (30) ◽  
Author(s):  
Yanath Belguesmia ◽  
Valérie Leclère ◽  
Matthieu Duban ◽  
Eric Auclair ◽  
Djamel Drider
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacterium ◽  
Enterococcus Faecalis ◽  
Genome Sequence ◽  
Draft Genome ◽  
Draft Genome Sequence ◽  
Coding Sequences ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
Healthy Newborn

ABSTRACT We report the draft genome sequence of Enterococcus faecalis DD14, a strain isolated from meconium of a healthy newborn at Roubaix Hospital (France). The strain displayed antagonism against a set of Gram-positive bacteria through concomitant production of lactic acid and bacteriocin. The genome has a size of 2,893,365 bp and a 37.3% G+C ratio and is predicted to contain at least 2,755 coding sequences and 62 RNAs.

scholarly journals Effects of Saline, an Ambient Acidic Environment, and Sodium Salicylate on OXA-Mediated Carbapenem Resistance in Acinetobacter baumannii: TABLE 1

2016 ◽  
Vol 60 (6) ◽  
pp. 3415-3418 ◽  
Author(s):  
Esther Zander ◽  
Harald Seifert ◽  
Paul G. Higgins
Keyword(s):  
Gene Expression ◽  
Acinetobacter Baumannii ◽  
Sodium Salicylate ◽  
Carbapenem Resistance ◽  
Low Ph ◽  
Wild Type ◽  
Experimental Conditions ◽  
Content Type ◽  
Reference Strains

Different physiological conditions, such as NaCl, low pH, and sodium salicylate, have been shown to affect antibiotic resistance determinants inAcinetobacter baumanniiisolates. Therefore, the aim of this study was to investigate the effects of NaCl, sodium salicylate, and low pH on the susceptibility ofA. baumanniito carbapenem. We cloned genes encoding oxacillinases (OXA) of different subclasses, with their associated promoters, from carbapenem-resistantA. baumanniiisolates into the same vector and transferred them to theA. baumanniireference strains ATCC 19606 and ATCC 17978. Carbapenem MICs were determined at least in triplicate by agar dilution under standard conditions, as well as in the presence of 200 mM NaCl or 16 mM sodium salicylate, or at pH 5.8. OXA-58-like gene expression was determined by reverse transcription-quantitative PCR (qRT-PCR). Under some experimental conditions, significant MIC reductions were shown for some transformants but not for others. Only in one instance were all transformants harboring the same OXA affected by the same condition: at pH 5.8, the imipenem and meropenem MICs for strains expressing OXA-58-like enzymes decreased from a resistant level (32 to 64 mg/liter) to an intermediate-susceptible level (8 mg/liter). However,blaOXA-58-likegene expression remained the same. MICs for both wild-type reference strains were not affected by the conditions tested. Our results indicate that the effects of the experimental conditions tested on OXAin vivoare mostly strain dependent. MICs were not reduced to wild-type levels, suggesting that the conditions tested do not lead to complete OXA inhibition in the bacterial cell.

Characterization of a new virulent phage infecting the lactic acid bacterium Oenococcus oeni

2016 ◽  
Vol 54 ◽  
pp. 167-177 ◽  
Author(s):  
Fety Jaomanjaka ◽  
Olivier Claisse ◽  
Mélanie Blanche-Barbat ◽  
Melina Petrel ◽  
Patricia Ballestra ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacterium ◽  
Oenococcus Oeni ◽  
Virulent Phage

scholarly journals Transcriptional Profiling of the Oral Pathogen Streptococcus mutans in Response to Competence Signaling Peptide XIP

mSystems ◽  
2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Iwona B. Wenderska ◽  
Andrew Latos ◽  
Benjamin Pruitt ◽  
Sara Palmer ◽  
Grace Spatafora ◽  
...  
Keyword(s):  
Gene Expression ◽  
Amino Acid ◽  
Stress Response ◽  
Heat Shock ◽  
Streptococcus Mutans ◽  
Potential Role ◽  
Stringent Response ◽  
Amino Acid Starvation ◽  
Genetic Competence ◽  
Content Type

ABSTRACT Genetic competence provides bacteria with an opportunity to increase genetic diversity or acquire novel traits conferring a survival advantage. In the cariogenic pathogen Streptococcus mutans, DNA transformation is regulated by the competence stimulating peptide XIP (ComX-inducing peptide). The present study utilizes high-throughput RNA sequencing (RNAseq) to provide a greater understanding of how global gene expression patterns change in response to XIP. Overall, our work demonstrates that in S. mutans, XIP signaling induces a response that resembles the stringent response to amino acid starvation. We further identify a novel heat shock-responsive intergenic region with a potential role in competence shutoff. Together, our results provide further evidence that multiple stress response mechanisms are linked through the genetic competence signaling pathway in S. mutans. In the cariogenic Streptococcus mutans, competence development is regulated by the ComRS signaling system comprised of the ComR regulator and the ComS prepeptide to the competence signaling peptide XIP (ComX-inducing peptide). Aside from competence development, XIP signaling has been demonstrated to regulate cell lysis, and recently, the expression of bacteriocins, small antimicrobial peptides used by bacteria to inhibit closely related species. Our study further explores the effect of XIP signaling on the S. mutans transcriptome. RNA sequencing revealed that XIP induction resulted in a global change in gene expression that was consistent with a stress response. An increase in several membrane-bound regulators, including HdrRM and BrsRM, involved in bacteriocin production, and the VicRKX system, involved in acid tolerance and biofilm formation, was observed. Furthermore, global changes in gene expression corresponded to changes observed during the stringent response to amino acid starvation. Effects were also observed on genes involved in sugar transport and carbon catabolite repression and included the levQRST and levDEFG operons. Finally, our work identified a novel heat shock-responsive intergenic region, encoding a small RNA, with a potential role in competence shutoff. IMPORTANCE Genetic competence provides bacteria with an opportunity to increase genetic diversity or acquire novel traits conferring a survival advantage. In the cariogenic pathogen Streptococcus mutans, DNA transformation is regulated by the competence stimulating peptide XIP (ComX-inducing peptide). The present study utilizes high-throughput RNA sequencing (RNAseq) to provide a greater understanding of how global gene expression patterns change in response to XIP. Overall, our work demonstrates that in S. mutans, XIP signaling induces a response that resembles the stringent response to amino acid starvation. We further identify a novel heat shock-responsive intergenic region with a potential role in competence shutoff. Together, our results provide further evidence that multiple stress response mechanisms are linked through the genetic competence signaling pathway in S. mutans.

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