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1.
Int J Mol Sci ; 25(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38674024

RESUMO

The COVID-19 pandemic prompted rapid research on SARS-CoV-2 pathogenicity. Consequently, new data can be used to advance the molecular understanding of SARS-CoV-2 infection. The present bioinformatics study discusses the "spikeopathy" at the molecular level and focuses on the possible post-transcriptional regulation of the SARS-CoV-2 spike protein S1 subunit in the host cell/tissue. A theoretical protein-RNA recognition code was used to check the compatibility of the SARS-CoV-2 spike protein S1 subunit with mRNAs in the human transcriptome (1-L transcription). The principle for this method is elucidated on the defined RNA binding protein GEMIN5 (gem nuclear organelle-associated protein 5) and RNU2-1 (U2 spliceosomal RNA). Using the method described here, it was shown that 45% of the genes/proteins identified by 1-L transcription of the SARS-CoV-2 spike protein S1 subunit are directly linked to COVID-19, 39% are indirectly linked to COVID-19, and 16% cannot currently be associated with COVID-19. The identified genes/proteins are associated with stroke, diabetes, and cardiac injury.


Assuntos
COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Humanos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , COVID-19/virologia , COVID-19/metabolismo , COVID-19/genética , Transcrição Gênica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Biologia Computacional/métodos , Transcriptoma
2.
Front Biosci (Landmark Ed) ; 28(11): 292, 2023 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-38062843

RESUMO

BACKGROUND: As a chronic degenerative disorder of the central nervous system that affects both motor and non-motor systems, Parkinson's disease (PD) is very complex, and explanations and models are needed to better understand how dopaminergic neurons are affected and microglia are activated. METHODS: A theoretical protein-RNA recognition code that assumes that the second letter in codons is compatible with specific amino acids involved in protein-RNA recognition was used to search for compatibility of human α-synuclein (α-syn) with mRNAs in the human transcriptome (1-L transcription). RESULTS: The 1-L transcription revealed compatible amino acid sequences with the ATTTA ARE (class I), PAS and polyA in α-syn, supporting a protein-RNA regulatory model. In PD, inflammatory microglia reactions, cognitive decline and motor circuit disturbances are observed. The model theoretically explains why α-syn producing neurons are less protected from inflammation and why microglia are activated. Consistent with knowledge of PD, the identified genes showed how the PI3K-AKT pathway is downregulated, how reactive oxygen species (ROS) production and sensitivity are increased, how mitochondria are destabilized, why autophagy is impaired, and why neuronal depigmentation is observed. CONCLUSIONS: 1-L transcription of α-syn leads to genes/proteins relevant to PD. When α-syn is accepted as a small RNA recognition protein involved in the post-transcriptional regulations, some identified genes indicate that its function is an important regulatory factor associated with intracellular and extracellular transport of RNA vesicles. These vesicles are extremely important in cellular communication. In addition, the spectrum of identified genes strongly indicates that α-syn produced by neuronal cells is required for proper regulation of inflammatory and immune responses.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Regulação da Expressão Gênica , Inflamação/genética , Inflamação/metabolismo , Neurônios Dopaminérgicos/metabolismo , RNA/metabolismo
3.
Life (Basel) ; 13(8)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37629477

RESUMO

Galactooligosaccharides obtained via ß-galactosidase transgalactosylation have health-promoting properties and are widely recognized as effective prebiotics. Trehalose-based galactooligosaccharides could be introduced into food and pharmaceutical industries similarly to trehalose. In light of this, new technological approaches are needed. Recently, in vivo enzyme immobilizations for recombinant proteins have been introduced, and physiological aggregation into active inclusion bodies (aIBs) has emerged as one such method of in vivo immobilization. To prepare LacZ ß-galactosidase in the form of aIBs, we used a short 10 amino acid aggregation-prone tag. These native protein particles were simply washed from the cell lysate and applied in trehalose galactosylation in a recycled batch mode. In this study, aIBs entrapped in alginate beads, encapsulated in alginate/cellulose sulfate/poly(methylene-co-guanidine) capsules and magnetized were compared with free aIBs. Alginate/cellulose sulfate/PMCG capsules showed more suitable properties and applicability for biotransformation of trehalose at its high concentration (25%, w/v) and elevated temperature (50 °C).

4.
Curr Issues Mol Biol ; 44(8): 3533-3551, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36005139

RESUMO

Alzheimer's disease is a very complex disease and better explanations and models are needed to understand how neurons are affected and microglia are activated. A new model of Alzheimer's disease is presented here, the ß-amyloid peptide is considered an important RNA recognition/binding peptide. 1-L transcription revealed compatible sequences with AAUAAA (PAS signal) and UUUC (class III ARE rich in U) in the Aß peptide, supporting the peptide-RNA regulatory model. When a hypothetical model of fibril selection with the prionic character of amyloid assemblies is added to the peptide-RNA regulatory model, the downregulation of the PI3K-Akt pathway and the upregulation of the PLC-IP3 pathway are well explained. The model explains why neurons are less protected from inflammation and why microglia are activated; why mitochondria are destabilized; why the autophagic flux is destabilized; and why the post-transcriptional attenuation of the axonal signal "noise" is interrupted. For example, the model suggests that Aß peptide may post-transcriptionally control ELAVL2 (ELAV-like RNA binding protein 2) and DCP2 (decapping mRNA protein 2), which are known to regulate RNA processing, transport, and stability.

5.
Curr Issues Mol Biol ; 44(2): 791-816, 2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35723340

RESUMO

The theoretical protein-RNA recognition code was used in this study to research the compatibility of the SARS-CoV-2 envelope protein (E) with mRNAs in the human transcriptome. According to a review of the literature, the spectrum of identified genes showed that the virus post-transcriptionally promotes or represses the genes involved in the SARS-CoV-2 life cycle. The identified genes/proteins are also involved in adaptive immunity, in the function of the cilia and wound healing (EMT and MET) in the pulmonary epithelial tissue, in Alzheimer's and Parkinson's disease and in type 2 diabetes. For example, the E-protein promotes BHLHE40, which switches off the IL-10 inflammatory "brake" and inhibits antiviral THαß cells. In the viral cycle, E supports the COPII-SCAP-SREBP-HSP90α transport complex by the lowering of cholesterol in the ER and by the repression of insulin signaling, which explains the positive effect of HSP90 inhibitors in COVID-19 (geldanamycin), and E also supports importin α/ß-mediated transport to the nucleus, which explains the positive effect of ivermectin, a blocker of importins α/ß. In summary, transcription of the envelope protein by the 1-L protein-RNA recognition code leads to genes/proteins that are relevant to the SARS-CoV-2 life cycle and pathogenesis.

6.
Front Bioeng Biotechnol ; 10: 833192, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35299638

RESUMO

Inclusion bodies are typically ignored as they are considered unwanted protein waste generated by prokaryotic host cells during recombinant protein production or harmful protein inclusions in human cell biology. However, these protein particles may have applications for in vivo immobilization in industrial biocatalysis or as cell-tolerable protein materials for the pharmaceuticals industry and clinical development. Thus, there is a need to in vivo "pull-down" (insolubilize) soluble enzymes and proteins into inclusion bodies. Accordingly, in this study, sequences from the short-chain polyphosphatase ygiF were used to design pull-down tags capable of detecting (poly)-phosphates and metal ions. These tags were compared with the entire CHAD domain from Escherichia coli ygiF and SACS2 CHAD from Saccharolobus solfataricus. The results demonstrated that highly soluble green fluorescent protein variants could be pulled down into the inclusion bodies and could have modified sensitivity to metals and di-/tri-inorganic phosphates.

7.
Methods Mol Biol ; 2406: 501-515, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35089577

RESUMO

Biocatalysis and biotransformations have a broad application in industrial synthetic chemistry. In addition to the whole cell catalysis, purified recombinant enzymes are successfully used for biocatalysis of specific chemical reactions. In this contribution, we report characterization, immobilization, and application of several model target enzymes (D-amino acid oxidase, sialic acid aldolase, maltodextrin phosphorylase, polyphosphate kinase, UDP-glucose pyrophosphorylase) physiologically aggregated within inclusion bodies retaining their biological activity as immobilized biocatalysts.


Assuntos
Enzimas Imobilizadas , Corpos de Inclusão , Bactérias/química , Bactérias/metabolismo , Biocatálise , Biotransformação , Enzimas Imobilizadas/química
8.
Front Genet ; 12: 763995, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659373

RESUMO

In this conceptual review, based on the protein-RNA recognition code, some theoretical sequences were detected in the spike (S), membrane (M) and capsid (N) proteins that may post-transcriptionally regulate the host genes/proteins in immune homeostasis, pulmonary epithelial tissue homeostasis, and lipid homeostasis. According to the review of literature, the spectrum of identified genes/proteins shows that the virus promotes IL1α/ß-IL1R1 signaling (type 1 immunity) and immunity defense against helminths and venoms (type 2 immunity). In the alteration of homeostasis in the pulmonary epithelial tissue, the virus blocks the function of cilia and the molecular programs that are involved in wound healing (EMT and MET). Additionally, the protein-RNA recognition method described here identifies compatible sequences in the S1A-domain for the post-transcriptional promotion of PIKFYVE, which is one of the critical factors for SARS-CoV-2 entry to the host cell, and for the post-transcriptional repression of xylulokinase XYLB. A decrease in XYLB product (Xu5P) in plasma was proposed as one of the potential metabolomics biomarkers of COVID-19. In summary, the protein-RNA recognition code leads to protein genes relevant to the SARS-CoV-2 life cycle and pathogenesis.

9.
Life (Basel) ; 11(5)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922417

RESUMO

In modern protein-carbohydrate interactions, carbohydrate-aromatic contact with CH-π interactions are used. Currently, they are considered driving forces of this complexation. In these contacts, tryptophan, tyrosine, and histidine are preferred. In this study, we focus on primary prebiotic chemistry when only glycine, alanine, aspartic acid, and valine are available in polypeptides. In this situation, when the aromatic acids are not available, hydrogen-bonding aspartic acid must be used for monosaccharide complexation. It is shown here that (DAA)n polypeptides play important roles in primary "protein"-glucose recognition, that (DGG)n plays an important role in "protein"-ribose recognition, and that (DGA)n plays an important role in "protein"-galactose recognition. Glucose oxidase from Aspergillus niger, which still has some ancient prebiotic sequences, is chosen here as an example for discussion.

10.
Cell Mol Life Sci ; 76(11): 2043-2058, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980111

RESUMO

MicroRNAs are small endogenous RNAs that pair and bind to sites on mRNAs to direct post-transcriptional repression. However, there is a possibility that microRNAs directly influence protein structure and activity, and this influence can be termed post-translational riboregulation. This conceptual review explores the literature on neurodegenerative disorders. Research on the association between neurodegeneration and RNA-repeat toxicity provides data that support a protein-RNA recognition code. For example, this code explains why hnRNP H and SFPQ proteins, which are involved in amyotrophic lateral sclerosis, are sequestered by the (GGGGCC)n repeat sequence. Similarly, it explains why MNBL proteins and (CTG)n repeats in RNA, which are involved in myotonic dystrophy, are sequestered into RNA foci. Using this code, proteins involved in diseases can be identified. A simple protein BLAST search of the human genome for amino acid repeats that correspond to the nucleotide repeats reveals new proteins among already known proteins that are involved in diseases. For example, the (CAG)n repeat sequence, when transcribed into possible peptide sequences, leads to the identification of PTCD3, Rem2, MESP2, SYPL2, WDR33, COL23A1, and others. After confirming this approach on RNA repeats, in the next step, the code was used in the opposite manner. Proteins that are involved in diseases were compared with microRNAs involved in those diseases. For example, a reasonable correspondence of microRNA 9 and 107 with amyloid-ß-peptide (Aß42) was identified. In the last step, a miRBase search for micro-nucleotides, obtained by transcription of a prion amino acid sequence, revealed new microRNAs and microRNAs that have previously been identified as involved in prion diseases. This concept provides a useful key for designing RNA or peptide probes.


Assuntos
Código Genético , MicroRNAs/metabolismo , Repetições de Microssatélites , Processamento de Proteína Pós-Traducional , RNA Mensageiro/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Sítios de Ligação , Genoma Humano , Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/metabolismo , Humanos , Doença de Huntington/genética , Doença de Huntington/metabolismo , Doença de Huntington/patologia , MicroRNAs/genética , Distrofia Miotônica/genética , Distrofia Miotônica/metabolismo , Distrofia Miotônica/patologia , Fator de Processamento Associado a PTB/genética , Fator de Processamento Associado a PTB/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doenças Priônicas/genética , Doenças Priônicas/metabolismo , Doenças Priônicas/patologia , Ligação Proteica , RNA Mensageiro/genética
11.
Microb Cell Fact ; 17(1): 139, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30176877

RESUMO

BACKGROUND: Physiological aggregation of a recombinant enzyme into enzymatically active inclusion bodies could be an excellent strategy to obtain immobilized enzymes for industrial biotransformation processes. However, it is not convenient to recycle "gelatinous masses" of protein inclusion bodies from one reaction cycle to another, as high centrifugation forces are needed in large volumes. The magnetization of inclusion bodies is a smart solution for large-scale applications, enabling an easier separation process using a magnetic field. RESULTS: Magnetically modified inclusion bodies of UDP-glucose pyrophosphorylase were recycled 50 times, in comparison, inclusion bodies of the same enzyme were inactivated during ten reaction cycles if they were recycled by centrifugation. Inclusion bodies of sialic acid aldolase also showed good performance and operational stability after the magnetization procedure. CONCLUSIONS: It is demonstrated here that inclusion bodies can be easily magnetically modified by magnetic iron oxide particles prepared by microwave-assisted synthesis from ferrous sulphate. The magnetic particles stabilize the repetitive use of the inclusion bodies .


Assuntos
Biotransformação/fisiologia , Centrifugação/métodos , Corpos de Inclusão/metabolismo
12.
J Biotechnol ; 216: 116-24, 2015 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-26477829

RESUMO

Sialic acids are well known for their crucial roles in many physiological and pathological processes. Improvement in the efficacy of protein drugs, an increase in the anti-inflammatory activity of intravenous immunoglobulin, preparation of infant milk and the diagnosis of diseases are examples of why there is a need for efficient in vitro sialylation. Sialyltransferases are crucial enzymes for the synthesis of sialo-oligosaccharides. Here, we introduce a new α2,3-sialyltransferase from bacteria Bibersteinia trehalosi (BtST1), which is homological to sialyltransferase from Pasteurella multocida (PmST1), Pasteurella dagmatis (PdST1) and Haemophilus ducreyi (Hd0053). BtST1 is active in a wide pH range and shows considerable acceptor flexibility. Very good specific activities have been detected with lactose and LacNAc as acceptors, and these activities were comparable to those of efficient multifunctional PmST1 and higher than PdST1, Hd0053 and also PmST1 M144D which was constructed to decrease the high sialidase activity of PmST1. Testing of PmST1 mutant forms revealed that mutations that included S143 caused only the restriction of sialyltransferase activity, whereas mutations including G142 resulted in the loss of activity with lactose. BtST1 possesses only low sialidase and trans-sialidase activities that are comparable to mutant PmST1 M144D, which are detected only in the presence of CMP. The combination of large acceptor flexibility, high activity for lactose and LacNAc and naturally low sialidase activity make BtST1 an attractive enzyme for biotechnological applications.


Assuntos
Gammaproteobacteria/enzimologia , Pasteurella multocida/enzimologia , Sialiltransferases/genética , Sialiltransferases/metabolismo , Sequência de Aminoácidos , Eletroforese em Gel de Poliacrilamida , Glicoproteínas , Concentração de Íons de Hidrogênio , Cinética , Dados de Sequência Molecular , Mutação , Neuraminidase , Proteínas Recombinantes/isolamento & purificação , Sialiltransferases/química , Homologia Estrutural de Proteína , Especificidade por Substrato , Temperatura , Fatores de Tempo
13.
Biochim Biophys Acta ; 1850(9): 1942-52, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26145579

RESUMO

BACKGROUND: RNA-binding proteins, in cooperation with non-coding RNAs, play important roles in post-transcriptional regulation. Non-coding micro-RNAs control information flow from the genome to the glycome by interacting with glycan-synthesis enzymes. Glycan-binding proteins read the cell surface and cytoplasmic glycome and transfer signals back to the nucleus. The profiling of the protein-RNA and protein-glycan interactomes is of significant medicinal importance. SCOPE OF REVIEW: This review discusses the state-of-the-art research in the protein-RNA and protein-glycan recognition fields and proposes the application of amino acid codes in profiling and programming the interactomes. MAJOR CONCLUSIONS: The deciphered PUF-RNA and PPR-RNA amino acid recognition codes can be explained by the protein-RNA amino acid recognition hypothesis based on the genetic code. The tripartite amino acid code is also involved in protein-glycan interactions. At present, the results indicate that a system of four codons ("gnc", where n=g - guanine, c - cytosine, u - uracil or a - adenine) and four amino acids (G - glycine, A - alanine, V - valine, D - aspartic acid) could be the original genetic code that imprinted "rules" into both recognition processes. GENERAL SIGNIFICANCE: Amino acid recognition codes have provocative potential in the profiling and programming of the protein-RNA and protein-glycan interactomes. The profiling and even programming of the interactomes will play significant roles in diagnostics and the development of therapeutic procedures against cancer and neurodegenerative, developmental and other diseases.


Assuntos
Aminoácidos/genética , Código Genético , Polissacarídeos/metabolismo , Proteínas/metabolismo , RNA/metabolismo , Sequência de Aminoácidos , Animais , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Polissacarídeos/química , Estrutura Terciária de Proteína , Proteínas/química , RNA/química , Análise de Sequência de Proteína
14.
Methods Mol Biol ; 1258: 411-22, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25447879

RESUMO

Biocatalysis and biotransformations have a broad application in industrial synthetic chemistry. In addition to the whole cell catalysis, purified recombinant enzymes are successfully used for biocatalysis of specific chemical reactions. In this contribution, we report characterization, immobilization, and application of several model target enzymes (D-amino acid oxidase, sialic acid aldolase, maltodextrin phosphorylase, polyphosphate kinase) physiologically aggregated within inclusion bodies (IBs) retaining their biological activity as immobilized biocatalysts.


Assuntos
Bactérias/metabolismo , Corpos de Inclusão/metabolismo , Biocatálise , Catálise
15.
Methods Mol Biol ; 1200: 421-45, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25117256

RESUMO

This chapter would like to provide a short survey of the most promising concepts applied recently in analysis of glycoproteins based on lectins. The first part describes the most exciting analytical approaches used in the field of glycoprofiling based on integration of nanoparticles, nanowires, nanotubes, or nanochannels or using novel transducing platforms allowing to detect very low levels of glycoproteins in a label-free mode of operation. The second part describes application of recombinant lectins containing several tags applied for oriented and ordered immobilization of lectins. Besides already established concepts of glycoprofiling several novel aspects, which we think will be taken into account for future, more robust glycan analysis, are described including modified lectins, peptide lectin aptamers, and DNA aptamers with lectin-like specificity introduced by modified nucleotides. The last part of the chapter describes a novel concept of a glycocodon, which can lead to a better understanding of glycan-lectin interaction and for design of novel lectins with unknown specificities and/or better affinities toward glycan target or for rational design of peptide lectin aptamers or DNA aptamers.


Assuntos
Engenharia Genética/métodos , Glicômica/métodos , Lectinas/metabolismo , Aptâmeros de Peptídeos/metabolismo , Humanos , Proteínas Imobilizadas/química , Proteínas Imobilizadas/genética , Proteínas Imobilizadas/metabolismo , Lectinas/química , Lectinas/genética , Polissacarídeos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
16.
Biotechnol Lett ; 36(10): 2029-35, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24930102

RESUMO

Polyphosphate kinases 2 (PPK2) are key enzymes for polyphosphate utilisation in bacteria. The genome of Ruegeria pomeroyi, a marine α-proteobacterium, includes three Pseudomonas aeruginosa PPK2 homologs. We expressed these homologs in Escherichia coli as soluble proteins, purified the protein products and compared their metal, pH and nucleotide preferences. The optimal pH was 8.0 for SPO1727 and 9.0 for SPO1256. The SPO0224 gene product had two pH optima at eight and ten. The SPO0224 protein showed little dependence on metal presence, while SPO1256 required Mg(2+). SPO1727 required Mg(2+) but accepted other ions as well.


Assuntos
Alphaproteobacteria/enzimologia , Proteínas de Bactérias/biossíntese , Fosfatos/metabolismo , Fosfotransferases (Aceptor do Grupo Fosfato)/biossíntese , Alphaproteobacteria/metabolismo , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Magnésio/química , Fosfotransferases (Aceptor do Grupo Fosfato)/isolamento & purificação , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo
17.
J Theor Biol ; 343: 9-15, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24269806

RESUMO

In early papers, the intent was to find a simple protein-RNA/DNA recognition code. Many people expected a one-to-one correspondence between amino acids and nucleic bases, similar to the code that specifies how one DNA base pairs with another. Despite the lack of such a code, which was evident in the first crystal structures, researchers were indeed unwilling to give up on the idea. Despite the intense interest, a simple one-to-one correspondence has not materialised. The work presented here revisits this theme, and reports a general trend in which four elementary amino acids - G, A, V, and D - have a specific selectivity for four basic nucleotides - g, c, u, and a. During the evolution, as amino acid alphabets increased, new amino acids substituted G, A, V, D amino acids in way to keep hydropathic similarity and the selectivity to minimise errors in established RNA-protein interactions, 1-letter code was created. Additionally, the first nucleotide in codons is used for a 2-letter code. Protein-RNA recognition, visualised by these two code principles, uses a rotation of sensing and anti-sensing sequences in architecture of recognising peptides.


Assuntos
Código Genético , Proteínas/metabolismo , RNA de Transferência/metabolismo , Sequência de Aminoácidos , Aminoacil-tRNA Sintetases/química , Aminoacil-tRNA Sintetases/metabolismo , Sequência de Bases , Modelos Genéticos , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/metabolismo , Proteínas/química , RNA de Transferência/genética
18.
Microb Cell Fact ; 12: 16, 2013 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-23391325

RESUMO

BACKGROUND: Adhesins of pathogens recognise the glycans on the host cell and mediate adherence. They are also crucial for determining the tissue preferences of pathogens. Currently, glyco-nanomaterials provide potential tool for antimicrobial therapy. We demonstrate that properly glyco-tailored inclusion bodies can specifically bind pathogen adhesins and release therapeutic substances. RESULTS: In this paper, we describe the preparation of tailored inclusion bodies via the conjugation of indicator protein aggregated to form inclusion bodies with soluble proteins. Whereas the indicator protein represents a remedy, the soluble proteins play a role in pathogen recognition. For conjugation, glutaraldehyde was used as linker. The treatment of conjugates with polar lysine, which was used to inactivate the residual glutaraldehyde, inhibited unwanted hydrophobic interactions between inclusion bodies. The tailored inclusion bodies specifically interacted with the SabA adhesin from Helicobacter pylori aggregated to form inclusion bodies that were bound to the sialic acids decorating the surface of human erythrocytes. We also tested the release of indicator proteins from the inclusion bodies using sortase A and Ssp DNAB intein self-cleaving modules, respectively. Sortase A released proteins in a relatively short period of time, whereas the intein cleavage took several weeks. CONCLUSIONS: The tailored inclusion bodies are promising "nanopills" for biomedical applications. They are able to specifically target the pathogen, while a self-cleaving module releases a soluble remedy. Various self-cleaving modules can be enabled to achieve the diverse pace of remedy release.


Assuntos
Corpos de Inclusão/metabolismo , Adesinas Bacterianas/química , Adesinas Bacterianas/metabolismo , Aminoaciltransferases/metabolismo , Bactérias/metabolismo , Bactérias/patogenicidade , Proteínas de Bactérias/metabolismo , Cisteína Endopeptidases/metabolismo , Eritrócitos/imunologia , Eritrócitos/metabolismo , Proteínas de Escherichia coli/metabolismo , Glutaral/química , Helicobacter pylori/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Corpos de Inclusão/química , Lisina/química , Lisina/metabolismo , Nanoestruturas/química
19.
J Theor Biol ; 307: 193-204, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22609469

RESUMO

Hydrophobic cellular membranes separate cells from an environment that is generally based on water. Therefore, it is not surprising that hydrophilic glycans and glycoproteins are exposed on the lipidic surface of membranes and that the glycocalyx has evolved in all basic cell types. During the evolution of multicellular life, the surface exposed protein-glycan interactions were taken as the origin of the language of cell-cell communication. The bioinformatics analysis presented here reveals that the amino acid triplets, the glycocodons, can be deduced for each glycan letter (monosaccharide). This theory proposes to distinguish between the "sugar code" (the sugar sequence) and the "glycocode" (evolutionary selected amino acids recognising the mono-sugar). Similarly to genetic code, original glycocodons are related to G, A, V, and D amino acids. Modern glycocodons can be deduced from GAVD-glycocodons using hydropathic similarity. In general, the amino acid triplets can be assembled from one dipeptide that is specific to a monosaccharide plus a polar amino acid. This theory may shed a different light on the reason for WWD conservation in the active sites of oligosaccharyltransferases and for GGQ in the active sites of ribosomes.


Assuntos
Código Genético , Modelos Genéticos , Polissacarídeos/genética , Sequência de Aminoácidos , Campylobacter/enzimologia , Cristalização , Galectina 3/química , Glicocálix/química , Glicocálix/genética , Glicoproteínas/química , Glicoproteínas/metabolismo , Hexosiltransferases/química , Humanos , Lectinas/química , Proteínas de Membrana/química , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/metabolismo , Polissacarídeos/química , Pseudomonas syringae/metabolismo , Alinhamento de Sequência , Ficolinas
20.
Microb Cell Fact ; 10: 63, 2011 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-21816086

RESUMO

There are a several molecules on Earth that effectively store energy within their covalent bonds, and one of these energy-rich molecules is polyphosphate. In microbial cells, polyphosphate granules are synthesised for both energy and phosphate storage and are degraded to produce nucleotide triphosphate or phosphate. Energy released from these energetic carriers is used by the cell for production of all vital molecules such as amino acids, nucleobases, sugars and lipids. Polyphosphate chains directly regulate some processes in the cell and are used as phosphate donors in gene regulation. These two processes, energetic metabolism and regulation, are orchestrated by polyphosphate kinases. Polyphosphate kinases (PPKs) can currently be categorized into three groups (PPK1, PPK2 and PPK3) according their functionality; they can also be divided into three groups according their homology (EcPPK1, PaPPK2 and ScVTC). This review discusses historical information, similarities and differences, biochemical characteristics, roles in stress response regulation and possible applications in the biotechnology industry of these enzymes. At the end of the review, a hypothesis is discussed in view of synthetic biology applications that states polyphosphate and calcium-rich organelles have endosymbiotic origins from ancient protocells that metabolized polyphosphate.


Assuntos
Polifosfatos/metabolismo , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/fisiologia , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo , Fosfotransferases (Aceptor do Grupo Fosfato)/fisiologia , Polifosfatos/química , Estrutura Terciária de Proteína
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