Chemotaxis of fluorescent Pseudomonas spp. to soybean seed exudates in vitro and in soil

1985 ◽  
Vol 31 (6) ◽  
pp. 570-574 ◽  
Author(s):  
F. M. Scher ◽  
J. W. Kloepper ◽  
C. A. Singleton
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Root Colonization ◽  
Soybean Seed ◽  
New Method ◽  
Bacterial Suspension ◽  
Soybean Seeds ◽  
Fluorescent Pseudomonas ◽  
Colony Forming Units

Five seed-colonizing fluorescent Pseudomonas strains (RW1 to RW5) exhibited chemotaxis toward soybean seed exudates in 1-μL capillaries held for 30 min in an 8.0 log colony-forming units/mL bacterial suspension over the temperature range of 9 to 41 °C. Dialysis (6000 molecular weight cut-off) of exudate nullified its attractiveness to RW1; heating (121 °C, 15 min) of exudate had no effect. Several amino acids present in exudate induced a chemotactic response by RW1, and asparagine, threonine, and valine at levels in exudate were as attractive as exudate. No chemotaxis by RW1 was observed toward sugars present in exudate. RW1 to RW5 actively migrated 1 cm toward soybean seeds in soil as demonstrated by a new method. A nonmotile mutant of RW3 did not migrate in soil and no significant migration by strains was observed when no seed or exudate was present. It is suggested that chemotaxis of Pseudomonas toward seed exudates may be the first step in establishment of bacterial seed and root colonization in soil.

Trans-tegumental absorption of L-alanine and L-leucine by a monogenean, Diclidophora merlangi

Parasitology ◽  
1978 ◽  
Vol 76 (1) ◽  
pp. 29-37 ◽  
Author(s):  
D. W. Halton
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Amino Acid ◽  
Sea Water ◽  
Low Molecular Weight ◽  
Acid Uptake ◽  
Neutral Amino Acids ◽  
Freeze Dried ◽  
Significant Difference

SummaryAn in vitro investigation has been made of the relative roles of the gut and tegument in the absorption of the neutral amino acids L-alanine and L-leucine by a marine fish-gill parasite, Diclidophora merlangi. The use of ligatures to preclude oral ingestion of trace-labelled medium has proved inadequate, invariably damaging the tegument, as revealed by stereoscan electron microscopy, and resulting in artifactual levels of absorption. Three alternative procedures have given consistently reliable data on the route of entry of low molecular weight substrates. (1) Ultrastructural examination of worms previously incubated in electron-dense cationic tracers has shown that, in vitro, there is no oral intake of sea water. (2) The suspending of worms in trace-labelled medium with the mouth out of the medium and comparing amino acid uptake with that of worms totally immersed in medium has revealed no statistically significant difference in the absorption levels. (3) Application of section (freeze-dried) auto-radiography to detect diffusible isotope has demonstrated directly transtegumental absorption of a neutral amino acid. It is concluded from these experiments that Diclidophora has a tegumental transport system for absorbing certain neutral amino acids, and whilst, clearly, the worm is sanguinivorous and digests blood in a well-developed gut, it may also be capable of supplementing this diet with low molecular weight organic nutrient absorbed directly from sea water via the tegument.

scholarly journals Adherence of Streptococcus mutans to Nanoceramic and Nanohybrid Resin Composites: An In vitro Study

2020 ◽  
pp. 128-133
Author(s):  
Krishnakanth Jaju ◽  
Iffat Nasim
Keyword(s):  
Streptococcus Mutans ◽  
Bacterial Adhesion ◽  
Resin Composite ◽  
In Vitro Study ◽  
Bacterial Suspension ◽  
Resin Composites ◽  
Colony Forming Units ◽  
Significant Difference ◽  
Test Control

Streptococcus mutans (S. mutans) is one of the cariogenic microorganisms. The restorative materials which harbor a biofilm with high number of S. mutans can accelerate the occurrence of dental caries. The purpose of this study was to evaluate the adherence of S. mutans to nanoceramic and nanohybrid resin composites. Fifteen discs of each material (Nanohybrid resin composite, Nanoceramic resin composite) were prepared, polished, and sterilized in a gamma radiation chamber. Specimens were exposed to the S. mutans bacterial suspension (0.5 McFarland) and were incubated for 4 hours. Specimens were rinsed and sonicated in normal saline, 10 μl of the obtained suspension was cultured in a sterile blood agar medium. After 24 hours, the number of colony forming units of S. mutans was counted. A sterility test control was considered for each group of materials. The data was analyzed by Independent t test. The means and standard deviations of the logarithmic counts of the colonies on the surfaces of nanohybrid resin composites and nanoceramic resin composite were equal to 3.2±0.87 and 2.8±0.324 respectively. Ceram X Universal did not show any significant difference in the bacterial adhesion compared to Filtek Z350XT. Both composites showed similar behaviour in terms of S. mutans colonization in a simple biofilm formation model.

scholarly journals Physicochemical Properties and Biological Activities of Silver Carp Scale Peptide and Its Nanofiltration Fractions

2022 ◽  
Vol 8 ◽  
Author(s):  
Xiao-yan Zu ◽  
Ya-jing Zhao ◽  
Shi-ming Fu ◽  
Tao Liao ◽  
Hai-lan Li ◽  
...  
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Physicochemical Properties ◽  
Biological Activities ◽  
Silver Carp ◽  
Radical Scavenging ◽  
Hydrophobic Amino Acids ◽  
Radical Scavenging Ability ◽  
Molecular Weight Fractions

To explore the physicochemical properties and biological functions of silver carp scale peptide (SCSP), its molecular-weight fractions SCSP-I, II, and III obtained by nanofiltration were assessed for their solubility, emulsibility, free radical scavenging ability, effect on the proliferation of mouse B16 cells. The results showed that the solubility of each fraction of SCSP was higher than 90%, SCSP-II and III were higher than 95%. The antioxidant powers on ⦁OH, O2-⦁ and Fe3+ were ranked as SCSP-III > SCSP-II > SCSP-I > SCSP. All fractions of SCSP had no toxic or side effects in mouse B16 melanoma cells experiments in vitro. At a concentration of 0.01 mg/mL, the tyrosinase activity of B16 cells in the SCSP-II fraction was significantly lower than that of the α-arbutin (P < 0.05), at 65.37%. The molecular weight distribution of SCSP was 399–1404 Dalton and 13 peptide sequences were detected. Among them, SCSP-II contained many hydrophobic amino acids, and SCSP-III stood out for combining arginine with hydrophobic amino acids. This may be the reason why the low molecular-weight SCSPs show the strong antioxidant activity and strong tyrosinase inhibition. The work provides a data base for the development of SCSP and increases the possibility of its application.

Isolation and characterization of full-length functional cDNA clones for human carcinoembryonic antigen

1987 ◽  
Vol 7 (9) ◽  
pp. 3221-3230
Author(s):  
N Beauchemin ◽  
S Benchimol ◽  
D Cournoyer ◽  
A Fuks ◽  
C P Stanners
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Amino Acid ◽  
Carcinoembryonic Antigen ◽  
Full Length ◽  
Cdna Clones ◽  
Base Pairs ◽  
Amino Terminal ◽  
Isolation And Characterization

Carcinoembryonic antigen (CEA) expression is perhaps the most prevalent of phenotypic changes observed in human cancer cells. The molecular genetic basis of this phenomenon, however, is completely unknown. Twenty-seven CEA cDNA clones were isolated from a human colon adenocarcinoma cell line. Most of these clones are full length and consist of a number (usually three) of surprisingly similar long (534 base pairs) repeats between a 5' end of 520 base pairs and a 3' end with three different termination points. The predicted translation product of these clones consists of a processed signal sequence of 34 amino acids, an amino-terminal sequence of 107 amino acids, which includes the known terminal amino acid sequence of CEA, three repeated domains of 178 amino acids each, and a membrane-anchoring domain of 27 amino acids, giving a total of 702 amino acids and a molecular weight of 72,813 for the mature protein. The repeated domains have conserved features, including the first 67 amino acids at their N termini and the presence of four cysteine residues. Comparisons with the amino acid sequences of other proteins reveals homology of the repeats with various members of the immunoglobulin supergene family, particularly the human T-cell receptor gamma chain. CEA cDNA clones in the SP-65 vector were shown to produce transcripts in vitro which could be translated in vitro to yield a protein of molecular weight 73,000 which in turn could be precipitated with CEA-specific antibodies. CEA cDNA clones were also inserted into an animal cell expression vector and introduced by transfection into mammalian cell lines. These transfectants produced a CEA-immunoprecipitable glycoprotein which could be visualized by immunofluorescence on the cell surface.

scholarly journals Isolation and characterization of full-length functional cDNA clones for human carcinoembryonic antigen.

1987 ◽  
Vol 7 (9) ◽  
pp. 3221-3230 ◽  
Author(s):  
N Beauchemin ◽  
S Benchimol ◽  
D Cournoyer ◽  
A Fuks ◽  
C P Stanners
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Amino Acid ◽  
Carcinoembryonic Antigen ◽  
Full Length ◽  
Cdna Clones ◽  
Base Pairs ◽  
Amino Terminal ◽  
Isolation And Characterization

Carcinoembryonic antigen (CEA) expression is perhaps the most prevalent of phenotypic changes observed in human cancer cells. The molecular genetic basis of this phenomenon, however, is completely unknown. Twenty-seven CEA cDNA clones were isolated from a human colon adenocarcinoma cell line. Most of these clones are full length and consist of a number (usually three) of surprisingly similar long (534 base pairs) repeats between a 5' end of 520 base pairs and a 3' end with three different termination points. The predicted translation product of these clones consists of a processed signal sequence of 34 amino acids, an amino-terminal sequence of 107 amino acids, which includes the known terminal amino acid sequence of CEA, three repeated domains of 178 amino acids each, and a membrane-anchoring domain of 27 amino acids, giving a total of 702 amino acids and a molecular weight of 72,813 for the mature protein. The repeated domains have conserved features, including the first 67 amino acids at their N termini and the presence of four cysteine residues. Comparisons with the amino acid sequences of other proteins reveals homology of the repeats with various members of the immunoglobulin supergene family, particularly the human T-cell receptor gamma chain. CEA cDNA clones in the SP-65 vector were shown to produce transcripts in vitro which could be translated in vitro to yield a protein of molecular weight 73,000 which in turn could be precipitated with CEA-specific antibodies. CEA cDNA clones were also inserted into an animal cell expression vector and introduced by transfection into mammalian cell lines. These transfectants produced a CEA-immunoprecipitable glycoprotein which could be visualized by immunofluorescence on the cell surface.

Biofilm Formation on Voice Prostheses: In vitro Influence of Probiotics

2001 ◽  
Vol 110 (10) ◽  
pp. 946-951 ◽  
Author(s):  
Rolien H. Free ◽  
G. Jolanda Elving ◽  
Ranny van Weissenbruch ◽  
Henk J. Busscher ◽  
Henny C. vander Mei ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Saline Solution ◽  
Streptococcus Thermophilus ◽  
Probiotic Bacteria ◽  
Bacterial Suspension ◽  
Voice Prostheses ◽  
Colony Forming Units ◽  
Probiotic Strains ◽  
Phosphate Buffered Saline

In order to determine the influence of probiotic bacteria on biofilm formation on Groningen and Provox 2 voice prostheses in an artificial throat, we grew biofilms on both types of voice prostheses and exposed them 3 times daily to a probiotic bacterial suspension. As a control, we perfused an artificial throat with phosphate-buffered saline solution. Perfusion with Lactococcus lactis 53 suspension reduced the percentage numbers of bacteria and yeasts, respectively, on the Groningen prostheses to 17% and 22% and on the Provox 2 prostheses to 19% and 45%, compared to the number of colony-forming units on the control prosthesis, which was set at 100%. A suspension of Streptococcus thermophilus b reduced the percentage numbers of bacteria and yeasts, respectively, on the Groningen prostheses to 53% and 33% and on the Provox 2 prostheses to 14% and 0%, as compared to the control prosthesis. All other probiotic strains tested caused some reduction in the percentages of bacteria or yeasts, but strong differences between the types of prostheses were observed. In conclusion, L lactis 53 and S thermophilus b strongly reduce the occurrence of yeasts and bacteria in voice prosthetic biofilms.

scholarly journals Influence of the Sodium Salt of 3α,7α-Dihydroxy-12-Oxo-5β-Cholanate on Antimicrobial Activity of Ampicillin In Vitro

2018 ◽  
Vol 44 (1) ◽  
pp. 6
Author(s):  
Ljiljana Suvajdžić ◽  
Slobodan Gigov ◽  
Aleksandar Rašković ◽  
Srđan Stojanović ◽  
Maja Bekut ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Sodium Salt ◽  
Antimicrobial Effect ◽  
In Vivo Studies ◽  
Bacterial Suspension ◽  
Commercial Preparation ◽  
E Coli ◽  
Colony Forming Units

Background: Multiple resistances to antibiotics are an emergent problem worldwide. Scientists intensively search for new substances with the antimicrobial potential or the mode to restore the activity of old-generation antibiotics. Ampicillin is the antibiotic with the expanded range of antimicrobial activity, but its use has decreased due to the poor absorption and highly developed resistance. In vivo studies showed that ampicillin has better absorption and bioavailability if combined with bile acid salts. The aim of this study was to examine antimicrobial effects of ampicillin alone and its combination with semisynthetic monoketocholic acid salt (MKH) in vitro.Materials, Methods & Results: In this study, commercial preparation of ampicillin and sodium salt of 3α,7α-dihydroxy-12oxo-5β-cholanate were used. Their effects were evaluated on Escherichia coli (E. coli), Enterococcus faecalis (E. faecalis) and Enterococcus faecium (E. faecium), obtained from urine specimens of dogs with clinically manifested cystitis. The first two investigated strains were ampicillin-sensitive, while E. faecium was resistant to ampicillin. Modified macrodilution method according to Clinical and Laboratory Standards Institute Guidelines (M7-A8) was performed. Bacterial suspension equivalent to 0.5 McFarland was prepared in saline, compared to the standard (Biomerieux) ad oculi. The density was checked spectrophotometrically at a wavelength of 625 nm and adjusted if necessary to the desired absorbance from 0.08 to 0.1. The resultant suspension was diluted 1:100 and inoculated in test tubes. Number of bacteria was counted on Petri plates using dilutions from 10-3 to 10-7 in order to obtain valid and countable plates. One hundred microliters of appropriate dilutions were aseptically plated in triplicate onto nutrient agar. Plates were incubated on 37°C for 72 h, under aerobic conditions. The number of colony forming units (CFU) was determined by direct counting. As a valid for enumeration, we took plates with 30 to 300 CFU. Percentage of killed bacteria for ampicillin was from 69.33-95.19% for E. coli, 87.1296.92% for E. faecalis and 7.20-33.30% for E. faecium. Ampicillin applied in the combination with MKH killed 99.99% to 100% of E. coli, 94.59% to 99.91% of E. faecalis and 31.73% to 64.76% of E. faecium. Mean percentage of killed bacteria for ampicillin was 81.93% for E. coli, 91.64% for E. faecalis, and 18.13% for E. faecium, while in combination with MKH percentage was 99.96% for E. coli, 98.23% for E. faecalis and 47.54% for E. faecium.Discussion: Results are presented as pharmacological minimal inhibitory concentration (MIC) values. Ampicillin was applied at the concentration higher than the therapeutic one, which could explain high MIC values for E. coli and E. faecalis. The combination of ampicillin with MKH showed the best improvement of antimicrobial effect on E. faecium (Δ = 29.41%), isolate that was resistant to ampicillin when applied alone. In all the investigated isolates, the combinations with MKH were more effective than ampicillin administered alone. It seems that MKH demonstrates a synergistic antimicrobial activity with ampicillin in vitro, which considerably decreases MIC values for all investigated isolates. These results implicate that MKH could restore the previous activity of ampicillin against some bacteria, which could be a significant benefit for clinical practice.

scholarly journals Impact of exocrine pancreatic adaptation on in vitro protein digestibility

1993 ◽  
Vol 69 (2) ◽  
pp. 359-369 ◽  
Author(s):  
P. Valette ◽  
H. Malouin ◽  
T. Corring ◽  
L. Savoie
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Pancreatic Enzyme ◽  
Protein Digestibility ◽  
Low Molecular Weight ◽  
Rapeseed Proteins ◽  
Total Capacity ◽  
Kinetics Of

An in vitro enzymic method was used to study the kinetics of digestion of casein and rapeseed proteins. After a predigestion step with pepsin (EC 3.4.23.1), the protein substrates were submitted to a 24 h hydrolysis either with pancreatin or pancreatic juices of pigs adapted either to casein or rapeseed diets and whose enzyme activities were different. After 3, 6 and 24 h of in vitro digestion, dialysates were collected and analysed for content of nitrogen, amino acids and low-molecular-weight peptides. For a long-term hydrolysis (24 h), overall digestibility of both substrates was not affected by the composition of pancreatic enzyme mixtures. However, at the beginning of hydrolysis a significant effect of pancreatic juices was observed, i.e. individual amino acid digestibility was generally higher when casein pancreatic juice was used for hydrolysis and their relative pattern of release was modified. For both substrates the proportion of amino acids released as low-molecular-weight peptides was not affected by the enzyme mixture used and made up about two-thirds of the total digested material. It is concluded that exocrine pancreatic adaptation to protein sources does not affect the total capacity of protein digestion. However, the changes in initial kinetics of release of amino acids are more dependent on the nature of the protein tested than on the composition of pancreatic enzyme mixtures.

scholarly journals In-Depth Investigation of Low-Abundance Proteins in Matured and Filling Stages Seeds of Glycine max Employing a Combination of Protamine Sulfate Precipitation and TMT-Based Quantitative Proteomic Analysis

Cells ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 1517 ◽  
Author(s):  
Cheol Woo Min ◽  
Joonho Park ◽  
Jin Woo Bae ◽  
Ganesh Kumar Agrawal ◽  
Randeep Rakwal ◽  
...  
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Large Scale ◽  
Storage Proteins ◽  
Soybean Seed ◽  
Proteome Analysis ◽  
Soybean Seeds ◽  
Differential Proteins ◽  
Seed Proteome ◽  
Abundance Proteins

Despite the significant technical advancements in mass spectrometry-based proteomics and bioinformatics resources, dynamic resolution of soybean seed proteome is still limited because of the high abundance of seed storage proteins (SSPs). These SSPs occupy a large proportion of the total seed protein and hinder the identification of low-abundance proteins. Here, we report a TMT-based quantitative proteome analysis of matured and filling stages seeds of high-protein (Saedanbaek) and low-protein (Daewon) soybean cultivars by application of a two-way pre-fractionation both at the levels of proteins (by PS) and peptides (by basic pH reverse phase chromatography). Interestingly, this approach led to the identification of more than 5900 proteins which is the highest number of proteins reported to date from soybean seeds. Comparative protein profiles of Saedanbaek and Daewon led to the identification of 2200 and 924 differential proteins in mature and filling stages seeds, respectively. Functional annotation of the differential proteins revealed enrichment of proteins related to major metabolism including amino acid, major carbohydrate, and lipid metabolism. In parallel, analysis of free amino acids and fatty acids in the filling stages showed higher contents of all the amino acids in the Saedanbaek while the fatty acids contents were found to be higher in the Daewon. Taken together, these results provide new insights into proteome changes during filling stages in soybean seeds. Moreover, results reported here also provide a framework for systemic and large-scale dissection of seed proteome for the seeds rich in SSPs by two-way pre-fractionation combined with TMT-based quantitative proteome analysis.

PROTEIN BIOSYNTHESIS IN VITRO BY THE PARS INTERMEDIA OF THE MOUSE PITUITARY GLAND

1977 ◽  
Vol 72 (2) ◽  
pp. 173-179
Author(s):  
H. ISHERWOOD ◽  
V. F. THORNTON
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Protein Biosynthesis ◽  
Pars Intermedia ◽  
Secretory Product ◽  
Posterior Pituitary ◽  
Short Term ◽  
Pituitary Glands ◽  
Mouse Pituitary

SUMMARY During short-term incubations of isolated posterior pituitary glands of the mouse, isotopically labelled amino acids were incorporated into protein by the cells of the pars intermedia. Using labelled leucine, 5–10% of incorporated label was found in a protein (P1), with a molecular weight of about 75000. Protein P1 could be isolated from both fresh and incubated tissue, and was a normal and indeed major, secretory product of the pars intermedia, constituting more than 50% of the protein present.

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