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Biology subjects

Butenko, I. O.

Publications and source records attributed to Butenko, I. O..

6 recordsLinked to original sources

Direct empirical in-house assessment of peptide proteotypicity for targeted proteomics

In bottom-up proteomics peptide it was early shown that despite a certain protein is present in a sample, only a subset of its proteolytic peptide products will be detected with LC-MS analysis. Property of peptide being frequently detected given its source proteins identification was called proteotypicity. Much effort has been since applied to predict proteotypic peptides and summarize evidence on peptide detection. Nevertheless, when targeted proteomics method is being developed, prediction or inference from communal experience might be inaccurate and prior knowledge of true peptide proteotypicity in a selected setup for a selected population is necessary. In this work we test fully in-house approach for proteotypicity assessment including comprehensive peptide synthesis and detection verification. Proteotypicity and contribution of sample processing and biology-related factors are estimated in a model experiment for three plasma proteins, albumin, ceruloplasmin and C-reactive protein.

genomics↗

Quality control of blood plasma for mass-spectrometry proteomic research

Mishandling of samples during blood plasma preparation may lead to biases in proteomic analysis and false interpretation of data. Previous plasma proteome profiling study (Geyer, Mann et al., 2019) described proteins that may serve to indicate poor plasma sample quality. We have established a targeted quantitative method for three prominent panels of markers proposed by previous study for exclusion of hemolyzed and coagulation samples. We conducted a model experiment similar to Geyer, Mann et al., with both panoramic and targeted detection and investigated the feasibility of application internal control for hemolysis in targeted proteomic analysis by using incorrectly collected plasma. We propose to include plasma sample hemolysis assessment into standard MRM analysis and associated sample exclusion criteria.

systems biology↗

Addressing diagnostic gaps in thyroid pathology: a multiplex protein panel as an adjunctive tool for risk stratification and differentiation of thyroid neoplasms

Fine-needle aspiration biopsy of thyroid nodules frequently yields indeterminate results, leading to unnecessary diagnostic surgeries. We evaluated a targeted plasma proteomics approach to differentiate benign follicular thyroid adenoma (FTA) from malignant papillary thyroid carcinoma (PTC). Using LC-MRM mass spectrometry with stable isotope-labeled standards (SIS), we quantified a multiplex protein panel in plasma samples from 267 patients. The analytical workflow incorporated an MS-based assessment of preanalytical hemolysis to prevent bias associated with thyroid-related blood composition changes and multiple rounds of randomization allowed assessment of batch effects. While previously proposed low-abundance thyroid cancer markers were rarely detected in the cohort, a signature of high-abundance plasma proteins successfully stratified the patients. The malignant PTC phenotype was characterized by a significant increase in apolipoprotein A1 and myosin-9, along with elevated CD14 and kininogen-1. Benign FTA was associated with higher levels of acute-phase proteins, including ceruloplasmin and complement C1q subunit C. Simple PCRE model with 20 parameters based on 4 major plasma proteins allowed to build a classifier with specificity that can be adjusted with regard to epidemiology and medical resource. This study establishes a foundational mass spectrometry-based framework that utilizes systemic proteomic profiles to differentiate underlying pathologies and improve clinical decision-making regarding patient management. By enabling additional stratification of patients with Bethesda IV cytology, who are otherwise frequently subjected to unwarranted diagnostic operations, this multiplex MS approach provides a potential non-invasive triage tool to reduce unnecessary surgical interventions for indeterminate thyroid nodules.

systems biology↗

Non-Human Peptides Revealed in Blood Reflect the Composition of Small Intestine Microbiota

The previously underestimated effects of commensal gut microbiota on the human body are increasingly being investigated using omics. The discovery of active molecules of interaction between the microbiota and the host may be an important step towards elucidating the mechanisms of symbiosis. Here, we show that in the bloodstream of healthy people, there are over 900 peptides that are fragments of proteins from microorganisms which naturally inhabit human biotopes, including the intestinal microbiota. Absolute quantitation by multiple reaction monitoring has confirmed the presence of bacterial peptides in the blood plasma and serum in the range of approximately 0.1 nM to 1 M. The abundance of microbiota peptides reaches its maximum about 5h after a meal. Most of the peptides correlate with the bacterial composition of the small intestine and are likely obtained by hydrolysis of membrane proteins with trypsin, chymotrypsin and pepsin -- the main proteases of the gastrointestinal tract. The peptides have physicochemical properties allowing them selectively pass the intestinal mucosal barrier and resist fibrinolysis. Proposed approach to the identification of microbiota peptides in the blood may be useful for determining the microbiota composition of hard-to-reach intestinal areas and for monitoring the permeability of the intestinal mucosal barrier.

biochemistry↗

Snapper: a high-sensitive algorithm to detect methylation motifs based on Oxford Nanopore reads

The Oxford Nanopore technology has a great potential for the analysis of genome methylation, including full-genome methylome profiling. However, there are certain issues while identifying methylation motif sequences caused by low sensitivity of the currently available motif enrichment algorithms. Here, we present Snapper, a new highly-sensitive approach to extract methylation motif sequences based on a greedy motif selection algorithm. Snapper has shown higher enrichment sensitivity compared with the MEME tool coupled with Tombo or Nanodisco instruments, which was demonstrated on H. pylori strain J99 studied earlier using the PacBio technology. In addition, we used Snapper to characterize the total methylome of a new H.pylori strain A45. The analysis revealed the presence of at least 4 methylation sites that have not been described for H. pylori earlier. We experimentally confirmed a new CCAG-specific methyltransferase and indirectly inferred a new CCAAK-specific methyltransferase.

bioinformatics↗

Far beyond common leeching: insights into an ancient medical device through integrated omics data

Salivary cell secretion (SCS) plays a critical role in blood feeding by medicinal leeches, making them of use for certain medical purposes even today. We annotated the Hirudo medicinalis genome and performed RNA-seq on salivary cells isolated from three closely related leech species, H. medicinalis, Hirudo orientalis, and Hirudo verbana. Differential expression analysis verified by proteomics identified salivary cell-specific genes, many of which encode previously unknown salivary components. However, the genes encoding known anticoagulants were not differentially expressed in the salivary cells. The function-related analysis of the unique salivary cell genes enabled an update of the concept of interactions between salivary proteins and components of haemostasis. Thus, our study provides one of the most comprehensive knowledge of the genetic fundamentals of the blood-sucking lifestyle in leeches.

systems biology↗