Microarray-based transcriptome ofListeria monocytogenesadapted to sublethal concentrations of acetic acid, lactic acid, and hydrochloric acid

2012 ◽  
Vol 58 (9) ◽  
pp. 1112-1123 ◽  
Author(s):  
Girum Tadesse Tessema ◽  
Trond Møretrø ◽  
Lars Snipen ◽  
Even Heir ◽  
Askild Holck ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Hydrochloric Acid ◽  
Organic Acids ◽  
Compatible Solutes ◽  
Foodborne Pathogen ◽  
Acid Stress ◽  
Low Ph ◽  
Transcriptional Responses ◽  
Ph Stress

Listeria monocytogenes , an important foodborne pathogen, commonly encounters organic acids in food-related environments. The transcriptome of L. monocytogenes L502 was analyzed after adaptation to pH 5 in the presence of acetic acid, lactic acid, or hydrochloric acid (HCl) at 25 °C, representing a condition encountered in mildly acidic ready-to-eat food kept at room temperature. The acid-treated cells were compared with a reference culture with a pH of 6.7 at the time of RNA harvesting. The number of genes and magnitude of transcriptional responses were higher for the organic acids than for HCl. Protein coding genes described for low pH stress, energy transport and metabolism, virulence determinates, and acid tolerance response were commonly regulated in the 3 acid-stressed cultures. Interestingly, the transcriptional levels of histidine and cell wall biosynthetic operons were upregulated, indicating possible universal response against low pH stress in L. monocytogenes. The opuCABCD operon, coding proteins for compatible solutes transport, and the transcriptional regulator sigL were significantly induced in the organic acids, strongly suggesting key roles during organic acid stress. The present study revealed the complex transcriptional responses of L. monocytogenes towards food-related acidulants and opens the roadmap for more specific and in-depth future studies.

scholarly journals Transcriptomic Analysis of Pediococcus pentosaceus Reveals Carbohydrate Metabolic Dynamics Under Lactic Acid Stress

2021 ◽  
Vol 12 ◽  
Author(s):  
Dong Han ◽  
Qiaojuan Yan ◽  
Jun Liu ◽  
Zhengqiang Jiang ◽  
Shaoqing Yang
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Carbohydrate Metabolism ◽  
Stress Responses ◽  
Protective Efficacy ◽  
Acid Stress ◽  
Cell Factory ◽  
Transcriptional Responses ◽  
Pediococcus Pentosaceus ◽  
Ecological Fitness

Stress physiology of lactic acid bacteria (LAB) is crucial to their ecological fitness and applicational implications. As a self-imposed stress, lactic acid is the major final metabolic product of LAB and its accumulation can be detrimental to bacterial cells. However, the relationship between LAB carbohydrate metabolism, the primary energy supplying bioactivities, and lactic acid stress responses is not fully understood. Pediococcus pentosaceus has been recognized as an important cell factory and demonstrated probiotic activities. This study investigated behavior of P. pentosaceus under lactic and acetic acid stresses, particularly with supplementations of metabolizable carbohydrates. Lactic and acetic acid retain similar growth stagnation effect, and both resulted in cell death in P. pentosaceus. All metabolizable carbohydrates improved bacterial survival compared to lactic acid control, while xylooligosaccharides (XOS) exerted the highest viability protective efficacy, 0.82 log CFU/mL higher population survived than other carbohydrates after 30 h of incubation. RNA-seq pipeline showcased the intensive global transcriptional responses of P. pentosaceus to lactic acid, which caused significant regulations (more than 2 Log2 fold) of 16.5% of total mRNA coding genes. Glucose mainly led to gene suppressions (83 genes) while XOS led to gene up-regulations (19 genes) under lactic acid stress. RT-qPCR study found that RNA polymerase-centered transcriptional regulation is the primary regulatory approach in evaluated culture conditions. The synergy between lactic acid stress and carbohydrate metabolism should be attentively contemplated in future studies and applications.

Characterization of Low Salinity Stress in Vibrio parahaemolyticus

2012 ◽  
Vol 75 (2) ◽  
pp. 231-237 ◽  
Author(s):  
WEI SHEN HUANG ◽  
HIN-CHUNG WONG
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Stationary Phase ◽  
Salinity Stress ◽  
Vibrio Parahaemolyticus ◽  
Acid Stress ◽  
Low Ph ◽  
Exponential Phase ◽  
Low Salinity ◽  
Acetic Acid Treatment

Vibrio parahaemolyticus is a marine foodborne pathogenic bacterium commonly found in seawater or seafood. This bacterium often encounters low salinity stress when the contaminated seafood is washed with fresh water during food processing. This study was conducted to investigate the response of exponential- and stationary-phase cells of V. parahaemolyticus ST550 to lethal or sublethal low salinity. Tolerance to lethal low salinity (0.25% NaCl) was enhanced in V. parahaemolyticus cells in the exponential phase by previous adaptation in sublethal low salinity (0.6% NaCl). Low salinity–adapted cells in the exponential phase were also cross-protected against the challenge of lethal low pH, indifferent to heat, and sensitized to bile, acetic acid, and lactic acid stress. The adapted cells in the stationary phase were significantly protected against heat treatment at 44°C for 10 and 15 min, sensitized to bile and acetic acid treatment, and indifferent to low pH and lactic acid.

Effect of pH, Acidulant, Time, and Temperature on the Growth and Survival of Listeria monocytogenes

1989 ◽  
Vol 52 (8) ◽  
pp. 571-573 ◽  
Author(s):  
KENT M. SORRELLS ◽  
DAVIN C. ENIGL ◽  
JOHN R. HATFIELD
Keyword(s):  
Antimicrobial Activity ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Listeria Monocytogenes ◽  
Citric Acid ◽  
Hydrochloric Acid ◽  
Malic Acid ◽  
Incubation Temperature ◽  
Growth And Survival ◽  
Ph Values

The effect of different acids, pH, incubation time, and incubation temperature on the growth and survival of four strains of Listeria monocytogenes in tryptic soy broth was compared. Hydrochloric acid (HCl), acetic acid (AA), lactic acid (LA), malic acid (MA), and citric acid (CA) were used to acidify tryptic soy broth to pH values 4.4, 4.6, 4.8, 5.0, and 5.2 pH. Incubation times were 1, 3, 7, 14, and 28 d at 10, 25, and 35°C. The inhibition of L. monocytogenes in the presence of high acidity appears to be a function of acid and incubation temperature. Based on equal pH values, the antimicrobial activity is AA > LA > CA ≥ MA > HCl at all incubation times and temperatures. When based on equal molar concentration, the activity appeared to be CA ≥ MA > LA ≥ AA > HCl at 35 and 25°C, and MA > CA > AA ≥ LA > HCl at 10°C. Greatest antimicrobial activity occurred at 35°C. Greatest survival occurred at 10°C and greatest growth occurred at 25°C. Final pH of the medium was as low as 3.8 in HCl at 28 d. All strains grew well at pH values lower than the minimum previously reported (5.5–5.6).

GROWTH OF STAPHYLOCOCCUS AUREUS IN ACIDIFIED PASTEURIZED MILK1

1970 ◽  
Vol 33 (11) ◽  
pp. 516-520 ◽  
Author(s):  
T. E. Minor ◽  
E. H. Marth
Keyword(s):  
Staphylococcus Aureus ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Hydrochloric Acid ◽  
Ph Value ◽  
The Other ◽  
Antagonistic Effects ◽  
Pasteurized Milk ◽  
Ph Values ◽  
Effect On Growth

The effect of gradually reducing the pH of pasteurized milk with acetic, citric, hydrochloric, lactic, and phosphoric acids over periods of 4, 8, and 12 hr on growth of Staphylococcus aureus 100 in this substrate was determined. In addition, 1: 1 mixtures of lactic acid and each of the other acids, and of acetic and citric acids were evaluated for their effect on growth of this organism. To achieve a 90% reduction in growth over a 12 hr period, a final pH value of 5.2 was required for acetic, 4.9 for lactic, 4.7 for phosphoric and citric, and 4.6 for hydrochloric acid. A 99% reduction during a 12 hr period was obtained with a final pH value of 5.0 for acetic, 4.6 for lactic, 4.5 for citric, 4.1 for phosphoric, and 4.0 for hydrochloric acid. A pH value of 3.3 was required for a 99.9% reduction with hydrochloric acid, whereas the same effect was produced at a pH value of 4.9 with acetic acid. Correspondingly lower pH values were required to inhibit growth within 8 and 4 hr periods. Mixtures of acids adjusted to pH values at the borderline for growth (12 hr period) exhibited neither synergistic nor antagonistic effects between two acids.

Mitigating the Antimicrobial Activities of Selected Organic Acids and Commercial Sanitizers with Various Neutralizing Agents

2011 ◽  
Vol 74 (5) ◽  
pp. 820-825 ◽  
Author(s):  
YOEN JU PARK ◽  
JINRU CHEN
Keyword(s):  
Escherichia Coli ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Organic Acids ◽  
Shiga Toxin ◽  
Room Temperature ◽  
Sodium Thiosulfate ◽  
Antimicrobial Activities ◽  
Phosphate Buffered Saline ◽  
Lactic Acids

This study was conducted to evaluate the abilities of five neutralizing agents, Dey-Engley (DE) neutralizing broth (single or double strength), morpholinepropanesulfonic acid (MOPS) buffer, phosphate-buffered saline (PBS), and sodium thiosulfate buffer, in mitigating the activities of acetic or lactic acid (2%) and an alkaline or acidic sanitizer (a manufacturer-recommended concentration) againt the cells of Shiga toxin–producing Escherichia coli (STEC; n = 9). To evaluate the possible toxicity of the neutralizing agents to the STEC cells, each STEC strain was exposed to each of the neutralizing agents at room temperature for 10 min. Neutralizing efficacy was evaluated by placing each STEC strain in a mixture of sanitizer and neutralizer under the same conditions. The neutralizing agents had no detectable toxic effect on the STEC strains. PBS was least effective for neutralizing the activity of selected organic acids and sanitizers. Single-strength DE and sodium thiosulfate neutralized the activity of both acetic and lactic acids. MOPS buffer neutralized the activity of acetic acid and lactic acid against six and five STEC strains, respectively. All neutralizing agents, except double-strength DE broth, had a limited neutralizing effect on the activity of the commercial sanitizers used in the study. The double-strength DE broth effectively neutralized the activity of the two commercial sanitizers with no detectable toxic effects on STEC cells.

Transcriptional profiling reveals molecular basis and the role of arginine in response to low-pH stress in Pichia kudriavzevii

2019 ◽  
Author(s):  
Hao Ji ◽  
Xiameng Dong ◽  
Kailun Zhang ◽  
Libo Jin ◽  
Renyi Peng ◽  
...  
Keyword(s):  
Organic Acids ◽  
Molecular Basis ◽  
Transcriptional Profiling ◽  
Cell Aggregation ◽  
Membrane Lipid ◽  
Low Ph ◽  
Pichia Kudriavzevii ◽  
Ph Stress ◽  
Ph Conditions

Abstract BackgroundThe non-conventional yeast Pichia kudriavzevii possesses a unique ability to tolerate various environmental stresses particularly low-pH stress. Thus, it is considered to be a promising biotechnological host for the production of various organic acids under low-pH conditions. However, little is known about the low-pH stress response in P. kudriavzevii, which significantly restricts its future development. ResultsIn this study, P. kudriavzevii JLY1107 showed great tolerance to low-pH stress, but its cell aggregation upon acidic conditions is unfavorable for the development of low-pH fermentation. To explore the molecular basis, we conducted RNA-Seq to compare global gene expression in response to low-pH. Among the 429 differentially expressed genes, the genes associated with regulation of membrane lipid composition, filamentous growth and arginine metabolism were selected for in-depth discussions. The up-regulation of genes associated with arginine uptake and degradation suggests a potential role of arginine in response to low-pH strsss. We therefore present data supporting the hypothesis that P. kudriavzevii maintains intracellular homeostasis by using the ammonia produced by arginine catabolism. Furthermore, external addition of arginine significantly enhances growth and reduces cell aggregation of P. kudriavzevii under low-pH conditions.ConclusionsArginine was demonstrated to be a promising molecule for improving cell growth and preventing cell aggregation under extremely low-pH conditions. Our study is a step towards developing the non-conventional yeast P. kudriavzevii as a platform host for the production of organic acids under low-pH conditions.

scholarly journals Biochemistry of waterlogged soils. Part III: Decomposition of carbohydrates with special reference to formation of organic acids

1929 ◽  
Vol 19 (4) ◽  
pp. 627-648 ◽  
Author(s):  
V. Subrahmanyan
Keyword(s):  
Carbon Dioxide ◽  
Organic Matter ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Organic Acids ◽  
Pyruvic Acid ◽  
Soluble Nitrogen ◽  
Direct Oxidation ◽  
Micro Organisms ◽  
Organic Matter Addition

(1) In absence of decomposing organic matter addition of nitrate led to no loss of nitrogen.(2) On addition of small quantities of fermentable matter such as glucose there was (a) rapid depletion of nitrates and oxygen, but no denitrification, and (b) increase in acidity, carbon dioxide and bacteria. The greater part of the soluble nitrogen was assimilated by microorganisms or otherwise converted and the greater part of the added carbohydrate was transformed into lactic, acetic and butyric acids.(3) The organic acids were formed from a variety of carbohydrates. Lactic acid was the first to be observed and appeared to be formed mainly by direct splitting of the sugar. It decomposed readily, forming acetic and butyric acids. Some acetic acid was formed by direct oxidation of lactic acid, with pyruvic acid as the intermediate product. All the acids were, on standing, converted into other forms by micro-organisms.

scholarly journals Impact of preoperative fecal short chain fatty acids on postoperative infectious complications in esophageal cancer patients

2019 ◽  
Author(s):  
Masaaki Motoori ◽  
Koji Tanaka ◽  
Keijiro Sugimura ◽  
Hiroshi Miyata ◽  
Takuro Saito ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Organic Acids ◽  
Propionic Acid ◽  
Butyric Acid ◽  
Bacterial Translocation ◽  
Infectious Complications ◽  
The Body ◽  
Intestinal Environment

Abstract Background: The intestinal epithelial barrier allows absorption of dietary nutrients and prevents passage of pathogens and toxins into the body. Severe insults have a negative impact on the intestinal environment, which may decrease intestinal barrier function and cause bacterial translocation. Bacterial translocation, which can cause infectious complications, is the passage of microbes from the gastrointestinal tract across the mucosal barrier to extraintestinal sites. The aim of this study was to investigate the correlation between concentrations of preoperative fecal organic acids and the occurrence of postoperative infectious complications in patients with esophageal cancer. Methods: Fifty-five patients with esophageal cancer who underwent esophagectomy were enrolled in this study. All patients were administered perioperative synbiotics. Perioperative clinical characteristics and concentrations of preoperative fecal organic acids were compared between patients with or without postoperative infectious complications. Results: Postoperative infectious complications occurred in 10 patients. In patients with complications, the concentrations of acetic acid and propionic acid were significantly lower than in patients without complications (p=0.044 and 0.032, respectively). The concentration of butyric acid was nonsignificantly lower, while the concentration of lactic acid was nonsignificantly higher in patients with complications. The calculated gap between the concentrations of fecal acetic acid plus propionic acid plus butyric acid minus lactic acid was significantly lower in patients with complications. Multivariate analysis revealed that a low gap between acetic acid plus propionic acid plus butyric acid minus lactic acid was an independent risk factor for postoperative infectious complications (p=0.027). Conclusions : Preoperative fecal concentrations of organic acids had a clinically important impact on the occurrence of postoperative infectious complications in patients with esophageal cancer. To reduce postoperative infectious complications, it may be useful to modulate the intestinal environment and maintain concentrations of fecal organic acids before surgery.

scholarly journals Impact of preoperative fecal short chain fatty acids on postoperative infectious complications in esophageal cancer patients

2020 ◽  
Author(s):  
Masaaki Motoori ◽  
Koji Tanaka ◽  
Keijiro Sugimura ◽  
Hiroshi Miyata ◽  
Takuro Saito ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Organic Acids ◽  
Propionic Acid ◽  
Butyric Acid ◽  
Bacterial Translocation ◽  
Infectious Complications ◽  
The Body ◽  
Intestinal Environment

Abstract Background: The intestinal epithelial barrier allows absorption of dietary nutrients and prevents passage of pathogens and toxins into the body. Severe insults have a negative impact on the intestinal environment, which may decrease intestinal barrier function and cause bacterial translocation. Bacterial translocation, which can cause infectious complications, is defined as the passage of microbes from the gastrointestinal tract across the mucosal barrier to extraintestinal sites. The aim of this study was to investigate the correlation between concentrations of preoperative fecal organic acids and the occurrence of postoperative infectious complications in patients with esophageal cancer. Methods: Fifty-five patients with esophageal cancer who underwent esophagectomy were enrolled in this study. Perioperative synbiotics were administered to all patients. Perioperative clinical characteristics and concentrations of preoperative fecal organic acids were compared between patients with and without postoperative infectious complications. Results: Postoperative infectious complications occurred in 10 patients. In patients with complications, the concentrations of acetic acid and propionic acid were significantly lower than in patients without complications (p=0.044 and 0.032, respectively). The concentration of butyric acid was nonsignificantly lower in patients with complications, while the concentration of lactic acid was nonsignificantly higher. The calculated gap between the concentrations of fecal acetic acid plus propionic acid plus butyric acid minus lactic acid was significantly lower in patients with complications. Multivariate analysis revealed that a low gap between acetic acid plus propionic acid plus butyric acid minus lactic acid was an independent risk factor for postoperative infectious complications (p=0.027). Conclusions : Preoperative fecal concentrations of organic acids had a clinically important impact on the occurrence of postoperative infectious complications in patients with esophageal cancer. To reduce postoperative infectious complications, it may be useful to modulate the intestinal environment and maintain concentrations of fecal organic acids before surgery.

scholarly journals Influences of Acid Catalysts on The Microstructure, Bioactivity and Cytotoxicity of Bioactive Glass Nanoparticles Prepared by Spray Pyrolysis

2020 ◽  
Author(s):  
Chao-Kuang Kuo ◽  
Liu-Gu Chen ◽  
Chun-Fu Tseng ◽  
Yu-Jen Chou
Keyword(s):  
Acetic Acid ◽  
Lactic Acid ◽  
Hydrochloric Acid ◽  
Bioactive Glass ◽  
Spray Pyrolysis ◽  
Material Science ◽  
Sol Gel ◽  
Drug Carriers ◽  
Acid Catalysts ◽  
Bioactive Glasses

Abstract Bioactive glasses have received considerable attention in the fields of medical and material science and have been applied in applications such as bone implants, tooth fillings, and drug carriers due to their high bioactivity, biocompatibility and biodegradability. Numerous studies applying either conventional glass processes or the sol-gel method have employed Hench's protocol for the fabrication of bioactive glass. However, the effects of various acid catalysts when using spray pyrolysis to synthesize bioactive glass remain unclear. Therefore, in this study, we synthesized bioactive glass nanoparticles using spray pyrolysis and then treated them with the acid catalysts hydrochloric acid, lactic acid and acetic acid. By characterizing the phase information and morphologies of the bioactive glass particles and examining their bioactivity and cytotoxicity, we found that the bioactive glass treated with hydrochloric acid yielded greater cell viability than the lactic acid- and acetic acid-treated specimens; the corresponding mechanisms are discussed in this paper.

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