Immunological activities of highly purified isoforms of human FSH correlate with in vitro bioactivities

1993 ◽  
Vol 139 (3) ◽  
pp. 511-518 ◽  
Author(s):  
P. G. Burgon ◽  
D. M. Robertson ◽  
P. G. Stanton ◽  
M. T. W. Hearn

ABSTRACT In a recent study, a five- to eightfold range in human FSH radioreceptor activity (RRA) was documented for highly purified isoforms of FSH when the data were expressed on an FSH protein content basis as determined by amino acid analysis. This study examined the FSH in vitro bioactivity and immunoactivity of these preparations. FSH in vitro biological activity showed a five- to eightfold range in activity with a high correlation with the RRA values (r=0·82). A similar five- to eightfold range of values was obtained with a specific FSH radioimmunoassay and an FSH two-site immunoassay with high correlations again observed between each other, between each immunoassay and with either the in vitro bioassay or the RRA method (r=0·77–0·995). Although there was overall a close correlation between these assays, significant differences in ratios of activities between the in vitro bioassay and other methods were observed with highly purified FSH isoform preparations from different pI regions. The high correlation between in vitro bioassay/RRA methods and immunoassay methods over a wide range of isoform specific activities suggests that these methods are detecting similar structural features on each isoform. It is thus concluded that these immunoassays are not solely measuring hormone mass based entirely on amino acid composition. This conclusion raises questions about ratio measurements of FSH, where immunoassay methods are presumed to measure total protein content, and their application in physiological situations and clinical practice. Journal of Endocrinology (1993) 139, 511–518

Foods ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1773
Author(s):  
Andrea Fuso ◽  
Silvia Barbi ◽  
Laura Ioana Macavei ◽  
Anna Valentina Luparelli ◽  
Lara Maistrello ◽  
...  

Insects are becoming increasingly relevant as protein sources in food and feed. The Black Soldier Fly (BSF) is one of the most utilized, thanks to its ability to live on many leftovers. Vegetable processing industries produce huge amounts of by-products, and it is important to efficiently rear BSF on different substrates to assure an economical advantage in bioconversion and to overcome the seasonality of some leftovers. This work evaluated how different substrates affect the protein and amino acid content of BSF. BSF prepupae reared on different substrates showed total protein content varying between 35% and 49% on dry matter. Significant lower protein contents were detected in BSF grown on fruit by-products, while higher contents were observed when autumnal leftovers were employed. BSF protein content was mainly correlated to fibre and protein content in the diet. Among amino acids, lysine, valine and leucine were most affected by the diet. Essential amino acids satisfied the Food and Agricultural Organization (FAO) requirements for human nutrition, except for lysine in few cases. BSF could be a flexible tool to bio-convert a wide range of vegetable by-products of different seasonality in a high-quality protein-rich biomass, even if significant differences in the protein fraction were observed according to the rearing substrate.


2005 ◽  
Vol 33 (3) ◽  
pp. 207-213 ◽  
Author(s):  
Paul J. Dierickx

In our previously described Hep G2/24-hour/total protein assay, protein levels were measured by using the Lowry method. This assay was the best acute in vitro assay for the prediction of human toxicity within the Multicentre Evaluation of In Vitro Cytotoxicity (MEIC) study. In order to increase the MEIC data-base with a wider range of chemicals, we were interested in introducing the more practical 3-(4-carboxybenzoyl)-quinoline-2-carboxaldehyde (CBQCA) method for the quantification of the total protein content. Therefore, we investigated whether the same good results for the prediction of acute human toxicity would be obtained with the CBQCA method. The cells were treated for 24 hours, then cytotoxicity was determined by measuring the total protein content with CBQCA. The results were quantified by using the PI50c: the concentration (in mM) of test compound required to reduce the total protein content measured with the CBQCA-method by 50% as compared to the control cells. The results were compared with the PI50, the corresponding value when the Lowry method was used. A relatively low correlation was observed between PI50 and PI50c, reflecting the large and unexpected, differences when using the two protein assays. However, when comparing the log PI50c with the human toxicity, a correlation coefficient of r2 = 0.761 ( n = 44) was obtained for exactly the same series of MEIC chemicals. This value is clearly higher than that for the Lowry method ( r2 = 0.695). Compared to the Lowry method originally used, the Hep G2/24-hour/CBQCA total protein assay has the additional important advantage that it can be very easily adapted for large-scale analyses with robotic systems, including the on-line calculation of the results.


1984 ◽  
Vol 4 (12) ◽  
pp. 1009-1015 ◽  
Author(s):  
J. P. Bali ◽  
H. Mattras ◽  
A. Previero ◽  
M. A. Coletti-Previero

Rat blood was shown to contain an aminopeptidase which rapidly hydrolyses short peptides containing an aromatic amino acid as N-terminal residue. Using tetragastrin (Trp-Met-Asp-PheNH 2) as substrate, we showed that some amino acid hydroxamates inhibit rat aminopeptidase activity ‘in vitro’ in the following order: HTrpNHOH > HPheNHOH ≫ HAIaNHOH. The same hydroxamates markedly enhanced the biological activity of tetragastrin ‘in vivo’. The amplification of the secretory effect, correlated with the amount of the hydroxamate used, strongly suggests that these compounds can stabilize a number of active peptides in vivo by inhibiting their proteolytic degradation.


Proteins ◽  
1987 ◽  
pp. 37-44
Author(s):  
Edouard C. Nice ◽  
John A. Smith ◽  
Robert L. Moritz ◽  
Michael J. O’Hare ◽  
Philip S. Rudland ◽  
...  

Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2431
Author(s):  
Nicola Landi ◽  
Sara Ragucci ◽  
Antimo Di Maro

Cow, sheep and goat raw milk raised in Ailano and Valle Agricola territories (‘Alto Casertano’, Italy) were characterized (raw proteins, free and total amino acids content) to assess milk quality. Raw milk with the highest total protein content is sheep milk followed by goat and cow milk from both localities. Total amino acid content in cow, goat and sheep raw milk is 4.58, 4.81 and 6.62 g per 100 g, respectively, in which the most abundant amino acid is glutamic acid (~20.36 g per 100 g of proteins). Vice versa, the free amino acids content characteristic profiles are different for each species. In particular, the most abundant free amino acid in cow, sheep and goat raw milk is glutamic acid (9.07 mg per 100 g), tyrosine (4.72 mg per 100 g) and glycine (4.54 mg per 100 g), respectively. In addition, goat raw milk is a source of taurine (14.92 mg per 100 g), retrieved in low amount in cow (1.38 mg per 100 g) and sheep (2.10 mg per 100 g) raw milk. Overall, raw milk from ‘Alto Casertano’ show a high total protein content and are a good source of essential amino acids.


2021 ◽  
Author(s):  
Amrutha Bindu ◽  
Lakshmi Devi

Abstract The focus of present study was to characterize antimicrobial peptide produced by probiotic cultures, Enterococcus durans DB-1aa (MCC4243), Lactobacillus plantarum Cu2-PM7 (MCC4246) and Lactobacillus fermentum Cu3-PM8 (MCC4233) against Staphylococus aureus and E. coli. The growth kinetic assay revealed 24 h of incubation to be optimum for bacteriocin production. The partially purified compound after ion-exchange chromatography was found to be thermoresistant and stable under wide range of pH. The compound was sensitive to proteinase-K, but resistant to trypsin, a-amylase and lipase. The apparent molecular weight of bacteriocin from MCC4243 and MCC4246 was found to be 3.5 KDa. Translated partial amino acid sequence of plnA gene in MCC4246 displayed 48 amino acid sequences showing 100% similarity with plantaricin A of Lactobacillus plantarum (WP_0036419). The sequence revealed 7 β sheets, 6 α sheets, 6 predicted coils and 9 predicted turns. The functions on cytoplasm show 10.82 isoelectric point and 48.6% hydrophobicity. The molecular approach of using Geneious Prime software and protein prediction data base for characterization of bacteriocin is novel and predicts “KSSAYSLQMGATAIKQVKKLFKKWGW” as peptide responsible for antimicrobial activity. The study provides information about broad spectrum bacteriocin in native probiotic culture and paves a way towards its application in functional foods as biopreservative agents.


Author(s):  
Siyan Zhao ◽  
Chen Zhang ◽  
Matthew J. Rogers ◽  
Xuejie Zhao ◽  
Jianzhong He

As a group, Dehalococcoides dehalogenate a wide range of organohalide pollutants but the range of organohalide compounds that can be utilized for reductive dehalogenation differs among the Dehalococcoides strains. Dehalococcoides lineages cannot be reliably disambiguated in mixed communities using typical phylogenetic markers, which often confounds bioremediation efforts. Here, we describe a computational approach to identify Dehalococcoides genetic markers with improved discriminatory resolution. Screening core genes from the Dehalococcoides pangenome for degree of similarity and frequency of 100% identity found a candidate genetic marker encoding a bacterial neuraminidase repeat (BNR)-containing protein of unknown function. This gene exhibits the fewest completely identical amino acid sequences and among the lowest average amino acid sequence identity in the core pangenome. Primers targeting BNR could effectively discriminate between 40 available BNR sequences ( in silico ) and 10 different Dehalococcoides isolates ( in vitro ). Amplicon sequencing of BNR fragments generated from 22 subsurface soil samples revealed a total of 109 amplicon sequence variants, suggesting a high diversity of Dehalococcoides distributed in environment. Therefore, the BNR gene can serve as an alternative genetic marker to differentiate strains of Dehalococcoides in complicated microbial communities. Importance The challenge of discriminating between phylogenetically similar but functionally distinct bacterial lineages is particularly relevant to the development of technologies seeking to exploit the metabolic or physiological characteristics of specific members of bacterial genera. A computational approach was developed to expedite screening of potential genetic markers among phylogenetically affiliated bacteria. Using this approach, a gene encoding a bacterial neuraminidase repeat (BNR)-containing protein of unknown function was selected and evaluated as a genetic marker to differentiate strains of Dehalococcoides , an environmentally relevant genus of bacteria whose members can transform and detoxify a range of halogenated organic solvents and persistent organic pollutants, in complex microbial communities to demonstrate the validity of the approach. Moreover, many apparently phylogenetically distinct, currently uncharacterized Dehalococcoides were detected in environmental samples derived from contaminated sites.


1992 ◽  
Vol 75 (4) ◽  
pp. 734-737 ◽  
Author(s):  
Shahrokh Khanizadeh ◽  
Deborah Buszard ◽  
Constantinos G Zarkadas

Abstract Three methods (Kjeldahl, sulfuric acid-hydrogen peroxide, and summation of amino acid content) for determining and calculating the protein content of apple flower buds were compared. Quantitation of protein content based on summation of amino acids appears to be the most accurate method. A new nitrogen:protein conversion factor (5.51) was calculated based on total amino acid analysis. This new conversion factor could replace the conventional 6.25 factor for estimating total protein content of apple flower bud by the Kjeldahl method. However, Kjeldahl is not an accurate method for estimating protein content in apple flower bud tissue, regardless of the conversion factor, and probably would not be a good method for estimation of protein in other plant species.


1959 ◽  
Vol 13 (2) ◽  
pp. 132-150 ◽  
Author(s):  
C. R. Smith ◽  
M. C. Shekleton ◽  
I. A. Wolff ◽  
Quentin Jones

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