scholarly journals Identification of mucin degraders of the human gut microbiota

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Stefano Raimondi ◽  
Eliana Musmeci ◽  
Francesco Candeliere ◽  
Alberto Amaretti ◽  
Maddalena Rossi

AbstractMucins are large glycoproteins consisting of approximately 80% of hetero-oligosaccharides. Gut mucin degraders of healthy subjects were investigated, through a culture dependent and independent approach. The faeces of five healthy adults were subjected to three steps of anaerobic enrichment in a medium with sole mucins as carbon and nitrogen sources. The bacterial community was compared before and after the enrichment by 16S rRNA gene profiling. Bacteria capable of fermenting sugars, such as Anaerotruncus, Holdemania, and Enterococcaceae likely took advantage of the carbohydrate chains. Escherichia coli and Enterobacteriaceae, Peptococcales, the Coriobacteriale Eggerthella, and a variety of Clostridia such as Oscillospiraceae, Anaerotruncus, and Lachnoclostridium, significantly increased and likely participated to the degradation of the protein backbone of mucin. The affinity of E. coli and Enterobacteriaceae for mucin may facilitate the access to the gut mucosa, promoting gut barrier damage and triggering systemic inflammatory responses. Only three species of strict anaerobes able to grow on mucin were isolated from the enrichments of five different microbiota: Clostridium disporicum, Clostridium tertium, and Paraclostridium benzoelyticum. The limited number of species isolated confirms that in the gut the degradation of these glycoproteins results from cooperation and cross-feeding among several species exhibiting different metabolic capabilities.

2016 ◽  
Author(s):  
Wenfa Ng ◽  
Yen-Peng Ting

Microbes for environmental research should be cultured in growth media with characteristics (e.g., pH, ionic strength, and organic and ionic composition) as close to their original habitat as possible. Additionally, the medium should also enable high cell density to be obtained - needed for providing sufficient cells in subsequent experiments. This in-progress report describes the formulation of a medium with an environmentally-relevant composition (lack of complex organics), and that allows aerobic high cell density cultivation of Escherichia coli DH5α in shake flasks. The formulated medium comprises four components: a buffer system (K2HPO4: 12.54 g/L and KH2PO4: 2.31 g/L), vitamins (yeast extract: 12.0 g/L), salts (NaCl: 5.0 g/L and MgSO4: 0.24 g/L), and carbon and nitrogen sources (D-Glucose: 6.0 g/L and NH4Cl: 1.5 g/L). Notable characteristics of this medium were: high capacity phosphate buffer system (89 mM phosphate); 1:1 molar ratio between D-Glucose and NH4Cl; and yeast extract providing trace elements and a secondary carbon and nitrogen source. Growth experiments revealed that an OD600nm of 9 was attained after 24 hours of cultivation at 37 oC. Glucose and NH4Cl serve as primary carbon and nitrogen sources for this phase of growth. After 48 hours, the OD600nm reached 11, where carbohydrates, lipids and proteins in yeast extract provided the nutrients for biomass formation. Broth’s pH varied between 5.5 and 7.8 during cultivation, which was in the range conducive for E. coli growth. In comparison, the OD600nm of E. coli reached 1.4, 3.2, and 9.2 in three commonly used complex media; Nutrient Broth, LB Lennox, and Tryptic Soy Broth, respectively, over 48 hours under identical culture conditions. In addition, the formulated medium was able to maintain a large viable cell population for a longer period of time (three days) compared to Tryptic Soy Broth. Thus, preliminary data suggested that the formulated medium holds potential for use as a high cell density aerobic growth medium for Gram-negative bacteria.


2020 ◽  
Vol 9 (11) ◽  
pp. e44891110235
Author(s):  
Rebeca Fasioli Silva ◽  
Maria do Socorro Mascarenhas Santos ◽  
Larissa Pires Mueller ◽  
Claudia Andrea Lima Cardoso ◽  
Margareth Batistote

The production of ethanol in Brazil is based on sugarcane juice, however other biomasses can be used for this process, such as sweet sorghum. However, some nutrients can interfere with fermentation, such as the presence of metals, carbon and nitrogen sources, which can affect the fermentation capacity of yeasts. Thus, this study aims to analyze the presence of fundamental nutrients present in saccharine substrates, as well as their assimilation and conversion of ethanol by the yeast Pedra-2. Samples of sugarcane and sorghum juice were obtained, in which analysis of the presence of metals was carried out using acid digestion and the levels determined by atomic flame absorption spectroscopy. The amino acid analysis was performed on the saccharine substrates at a concentration of 22 ºBrix, before and after fermentation, and analyzed by high-performance liquid chromatography and the concentration of ethanol by gas chromatography. The sorghum broth showed higher amounts of available amino acid metals. The yeast Pedra-2 showed better fermentative performance in the sorghum broth. We can conclude that the sorghum broth represents an important substrate to be used to increase the sustainability and production of ethanol in Brazil.


2021 ◽  
Author(s):  
R Rajendran ◽  
S Kiruthika ◽  
P Saranya ◽  
Arunkumar Mohan ◽  
C V Vaishali

Abstract Discharge of the untreated wastewater containing dyestuff into the surrounding aquatic environment is of significant environmental concern. These dying effluents not only change the color of water bodies but also has many unfavorable conditions and release toxic by-products, which are mutagenic, carcinogenic, and hazardous to different life forms. The present study investigated the biodegradation and removal of dye mixture (Remazol Brilliant violet 5R and Reactive Red 120) using a new bacterial consortium isolated from dye contaminated soil. Among the total 15 isolates screened, the two most efficient bacterial species (SS07 and SS09) were selected and identified as Enterobacter cloacae (MT573884) and Achromobacter pulmonis (MT573885) through biochemical assays and 16S rRNA gene sequencing. The removal efficiency of dye mixture by Enterobacter cloacae and Achromobacter pulmonis at an initial concentration of 100 mg L− 1 was 82.78 and 84.96%, discretely. The bacterial consortium was developed using selected isolates, and the optimum conditions for the removal of dyes were investigated by studying the effects of pH, temperature, carbon and nitrogen sources, dye concentration, and inoculum size. The maximum decolorization efficiency was achieved at pH, 7; temperature, 37°C; dye concentration, 100 ppm; and initial inoculum concentration, 0.5 ml, respectively. Mannitol and Ammonium sulfate was identified as the most suitable carbon and nitrogen sources for better bacterial growth and decolorization. The maximum removal efficiency of 91.3% achieved at the optimal conditions after 72 h of incubation. Decolorization of azo dyestuff by the developed microbial consortia conforms to the zero-order reaction kinetics model. Consortia of Enterobacter cloacae and Achromobacter pulmonis was established as an effective decolorizer for the Remazol Brilliant violet 5R and Reactive Red 120 dye mixture with > 90% color removal.


2017 ◽  
Author(s):  
Wenfa Ng ◽  
Yen-Peng Ting

Microbes for environmental research should be cultured in growth media with characteristics (e.g., pH, ionic strength, and ionic composition) as close to their original habitat as possible. Additionally, the medium should also enable high cell density to be obtained, which is needed for providing sufficient cells in subsequent experiments. This in-progress report describes the formulation of a medium with an environmentally relevant composition (i.e., lack of complex organics), and that allows aerobic high cell density cultivation of Escherichia coli DH5α (ATCC 53868) in shake flasks. The formulated medium comprises four components: a buffer system (K2HPO4: 12.54 g/L and KH2PO4: 2.31 g/L), vitamins (yeast extract: 12.0 g/L), salts (NaCl: 5.0 g/L and MgSO4: 0.24 g/L), and carbon and nitrogen sources (D-Glucose: 6.0 g/L and NH4Cl: 1.5 g/L). Notable characteristics of this medium were: high capacity phosphate buffer system (89 mM phosphate); 1:1 molar ratio between D-Glucose and NH4Cl; and yeast extract providing trace elements and a secondary carbon and nitrogen source. Growth experiments revealed that an OD600nm of 9 was obtained after 24 hours of cultivation at 37 oC. Glucose and NH4Cl served as primary carbon and nitrogen sources for this growth phase. After 48 hours, the OD600nm reached 11, where carbohydrates, lipids and proteins in yeast extract provided the nutrients for biomass formation. Broth’s pH varied between 5.5 and 7.8 during cultivation, which is conducive for E. coli growth. In comparison, the OD600nm of E. coli reached 1.4, 3.2, and 9.2 in three commonly used complex media; Nutrient Broth, LB Lennox, and Tryptic Soy Broth, respectively, over 48 hours under identical culture conditions. In addition, the formulated medium was able to maintain a large viable cell population for a longer period of time (three days) compared to Tryptic Soy Broth. Thus, preliminary data suggested that the formulated medium holds potential for use as a high cell density aerobic growth medium for Gram-negative bacteria.


2017 ◽  
Author(s):  
Wenfa Ng ◽  
Yen-Peng Ting

Microbes for environmental research should be cultured in growth media with characteristics (e.g., pH, ionic strength, and ionic composition) as close to their original habitat as possible. Additionally, the medium should also enable high cell density to be obtained, which is needed for providing sufficient cells in subsequent experiments. This in-progress report describes the formulation of a medium with an environmentally relevant composition (i.e., lack of complex organics), and that allows aerobic high cell density cultivation of Escherichia coli DH5α (ATCC 53868) in shake flasks. The formulated medium comprises four components: a buffer system (K2HPO4: 12.54 g/L and KH2PO4: 2.31 g/L), vitamins (yeast extract: 12.0 g/L), salts (NaCl: 5.0 g/L and MgSO4: 0.24 g/L), and carbon and nitrogen sources (D-Glucose: 6.0 g/L and NH4Cl: 1.5 g/L). Notable characteristics of this medium were: high capacity phosphate buffer system (89 mM phosphate); 1:1 molar ratio between D-Glucose and NH4Cl; and yeast extract providing trace elements and a secondary carbon and nitrogen source. Growth experiments revealed that an OD600nm of 9 was obtained after 24 hours of cultivation at 37 oC. Glucose and NH4Cl served as primary carbon and nitrogen sources for this growth phase. After 48 hours, the OD600nm reached 11, where carbohydrates, lipids and proteins in yeast extract provided the nutrients for biomass formation. Broth’s pH varied between 5.5 and 7.8 during cultivation, which is conducive for E. coli growth. In comparison, the OD600nm of E. coli reached 1.4, 3.2, and 9.2 in three commonly used complex media; Nutrient Broth, LB Lennox, and Tryptic Soy Broth, respectively, over 48 hours under identical culture conditions. In addition, the formulated medium was able to maintain a large viable cell population for a longer period of time (three days) compared to Tryptic Soy Broth. Thus, preliminary data suggested that the formulated medium holds potential for use as a high cell density aerobic growth medium for Gram-negative bacteria.


2020 ◽  
Vol 12 (1) ◽  
pp. 154-171
Author(s):  
Oluwatoyin M. ALADEJANA ◽  
Olaoluwa OYEDEJI ◽  
Olumide OMOBOYE ◽  
Mufutau BAKARE

Amylases have wide biotechnological potentials for applications in various industries. An α-amylase-producing bacterium was isolated from deteriorating yam tubers. Molecular characterization using the 16S rRNA gene sequencing was used to confirm the identity of the bacterium as Bacillus subtilis Y25. The effect of some cultural and nutritional factors such as pH, temperature, carbon and nitrogen sources on α-amylase production from the bacterium was determined. Maximum α-amylase production was observed using starch and peptone as carbon and nitrogen sources, respectively, with an initial medium pH of 8.0 and incubation at 45 °C for 36 h. The enzyme was purified by ion exchange chromatography on CM Sepharose CL-6B. The kinetic parameters Km and Vmax of the enzyme, as well as the effect of pH, temperature, metal ions and ethylenediaminetetra acetic acid (EDTA) on the activity of the purified enzyme were studied. The specific activity of the partially purified enzyme was determined to be 15.21 Units/mg protein with a purification fold of 3.80. The molecular weight of the purified enzyme was estimated to be 58.0 kDa. The Vmax and Km values obtained with soluble starch for Bacillus subtilis Y25 α-amylase were 314.10 ± 23.30 Units/mg protein and 53.98 ± 12.03 mg/ml, respectively. The enzyme exhibited optimum activity at a temperature of 60 °C and pH 8.0. The metal ion Ca2+ had no effect on the enzyme at 20 mM concentration, whereas Na+ and Mg2+, as well as EDTA inhibited the enzyme at the same concentration. The characteristics of the α-amylase from Bacillus subtilis Y25 revealed it to be a thermostable and an alkaline metalloenzyme with potential for applications in the detergent and saccharification industries.


2017 ◽  
Author(s):  
Wenfa Ng ◽  
Yen-Peng Ting

Microbes for environmental research should be cultured in growth media with characteristics (e.g., pH, ionic strength, and ionic composition) as close to their original habitat as possible. Additionally, the medium should also enable high cell density to be obtained, which is needed for providing sufficient cells in subsequent experiments. This in-progress report describes the formulation of a medium with an environmentally relevant composition (i.e., lack of complex organics), and that allows aerobic high cell density cultivation of Escherichia coli DH5α (ATCC 53868) in shake flasks. The formulated medium comprises four components: a buffer system (K2HPO4: 12.54 g/L and KH2PO4: 2.31 g/L), vitamins (yeast extract: 12.0 g/L), salts (NaCl: 5.0 g/L and MgSO4: 0.24 g/L), and carbon and nitrogen sources (D-Glucose: 6.0 g/L and NH4Cl: 1.5 g/L). Notable characteristics of this medium were: high capacity phosphate buffer system (89 mM phosphate); 1:1 molar ratio between D-Glucose and NH4Cl; and yeast extract providing trace elements and a secondary carbon and nitrogen source. Growth experiments revealed that an OD600nm of 9 was obtained after 24 hours of cultivation at 37 oC. Glucose and NH4Cl served as primary carbon and nitrogen sources for this growth phase. After 48 hours, the OD600nm reached 11, where carbohydrates, lipids and proteins in yeast extract provided the nutrients for biomass formation. Broth’s pH varied between 5.5 and 7.8 during cultivation, which is conducive for E. coli growth. In comparison, the OD600nm of E. coli reached 1.4, 3.2, and 9.2 in three commonly used complex media; Nutrient Broth, LB Lennox, and Tryptic Soy Broth, respectively, over 48 hours under identical culture conditions. In addition, the formulated medium was able to maintain a large viable cell population for a longer period of time (three days) compared to Tryptic Soy Broth. Thus, preliminary data suggested that the formulated medium holds potential for use as a high cell density aerobic growth medium for Gram-negative bacteria.


2016 ◽  
Author(s):  
Wenfa Ng ◽  
Yen-Peng Ting

Microbes for environmental research should be cultured in growth media with characteristics (e.g., pH, ionic strength, and organic and ionic composition) as close to their original habitat as possible. In addition, the medium should also enable high cell density to be obtained - needed for providing sufficient cells in subsequent experiments. This in-progress report describes the formulation of a medium with an environmentally-relevant composition (i.e., lack of complex organics), and that allows aerobic high cell density cultivation of Escherichia coli DH5α (ATCC 53868) in shake flasks. The formulated medium comprises four components: a buffer system (K2HPO4: 12.54 g/L and KH2PO4: 2.31 g/L), vitamins (yeast extract: 12.0 g/L), salts (NaCl: 5.0 g/L and MgSO4: 0.24 g/L), and carbon and nitrogen sources (D-Glucose: 6.0 g/L and NH4Cl: 1.5 g/L). Notable characteristics of this medium were: high capacity phosphate buffer system (89 mM phosphate); 1:1 molar ratio between D-Glucose and NH4Cl; and yeast extract providing trace elements and a secondary carbon and nitrogen source. Growth experiments revealed that an OD600nm of 9 was obtained after 24 hours of cultivation at 37 oC. Glucose and NH4Cl served as primary carbon and nitrogen sources for this phase of growth. After 48 hours, the OD600nm reached 11, where carbohydrates, lipids and proteins in yeast extract provided the nutrients for biomass formation. Broth’s pH varied between 5.5 and 7.8 during cultivation, which was in the range conducive for E. coli growth. In comparison, the OD600nm of E. coli reached 1.4, 3.2, and 9.2 in three commonly used complex media; Nutrient Broth, LB Lennox, and Tryptic Soy Broth, respectively, over 48 hours under identical culture conditions. In addition, the formulated medium was able to maintain a large viable cell population for a longer period of time (three days) compared to Tryptic Soy Broth. Thus, preliminary data suggested that the formulated medium holds potential for use as a high cell density aerobic growth medium for Gram-negative bacteria.


2018 ◽  
Vol 69 ◽  
pp. 1-11 ◽  
Author(s):  
Willian Daniel Hahn Schneider ◽  
Roselei Claudete Fontana ◽  
Simone Mendonça ◽  
Félix Gonçalves de Siqueira ◽  
Aldo José Pinheiro Dillon ◽  
...  

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