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Merz M, Schiffer CJ, Klingl A, Ehrmann MA. Characterization of the major autolysin (AtlC) of Staphylococcus carnosus. BMC Microbiol 2024; 24:77. [PMID: 38459514 PMCID: PMC10921637 DOI: 10.1186/s12866-024-03231-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 02/21/2024] [Indexed: 03/10/2024] Open
Abstract
BACKGROUND Autolysis by cellular peptidoglycan hydrolases (PGH) is a well-known phenomenon in bacteria. During food fermentation, autolysis of starter cultures can exert an accelerating effect, as described in many studies on cheese ripening. In contrast, very little is known about autolysis of starter cultures used in other fermentations. Staphylococcus (S.) carnosus is often used in raw sausage fermentations, contributing to nitrate reduction and flavor formation. In this study, we analyzed the influence of PGHs of the strains S. carnosus TMW 2.146 and S. carnosus TMW 2.2525 on their autolytic behavior. The staphylococcal major autolysin (Atl), a bifunctional enzyme with an N-acetylmuramoyl-L-alanine amidase and a glucosaminidase as an active site, is assumed to be the enzyme by which autolysis is mainly mediated. RESULTS AtlC mutant strains showed impaired growth and almost no autolysis compared to their respective wild-type strains. Light microscopy and scanning electron microscopy showed that the mutants could no longer appropriately separate from each other during cell division, resulting in the formation of cell clusters. The surface of the mutants appeared rough with an irregular morphology compared to the smooth cell surfaces of the wild-types. Moreover, zymograms showed that eight lytic bands of S. carnosus, with a molecular mass between 140 and 35 kDa, are processed intermediates of AtlC. It was noticed that additional bands were found that had not been described in detail before and that the banding pattern changes over time. Some bands disappear entirely, while others become stronger or are newly formed. This suggests that AtlC is degraded into smaller fragments over time. A second knockout was generated for the gene encoding a N-acetylmuramoyl-L-alanine amidase domain-containing protein. Still, no phenotypic differences could be detected in this mutant compared to the wild-type, implying that the autolytic activity of S. carnosus is mediated by AtlC. CONCLUSIONS In this study, two knockout mutants of S. carnosus were generated. The atlC mutant showed a significantly altered phenotype compared to the wild-type, revealing AtlC as a key factor in staphylococcal autolysis. Furthermore, we show that Atl is degraded into smaller fragments, which are still cell wall lytic active.
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Affiliation(s)
- Maximilian Merz
- Chair of Microbiology, Technical University of Munich, Gregor-Mendel-Straße 4, 85354, Freising, Germany
| | - Carolin J Schiffer
- Chair of Microbiology, Technical University of Munich, Gregor-Mendel-Straße 4, 85354, Freising, Germany
| | - Andreas Klingl
- Plant Development, Department Biology I - Botany, Ludwig-Maximilians-Universität München, Großhaderner Str. 2-4, 82152, Planegg-Martinsried, Germany
| | - Matthias A Ehrmann
- Chair of Microbiology, Technical University of Munich, Gregor-Mendel-Straße 4, 85354, Freising, Germany.
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Berneking L, Büttner H, Qi M, Günther T, Lehnhoff D, Both A, Christner M, Wolters M, Alawi M, Aepfelbacher M, Rohde H. Complete genome sequence of a Staphylococcus condimenti isolated from a port catheter-associated bloodstream infection. Microbiol Resour Announc 2023; 12:e0043823. [PMID: 37655888 PMCID: PMC10586149 DOI: 10.1128/mra.00438-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 06/30/2023] [Indexed: 09/02/2023] Open
Abstract
Here, we describe the complete genome sequence of a Staphylococcus condimenti blood culture isolate from a catheter-related bloodstream infection in a male patient.
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Affiliation(s)
- Laura Berneking
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Henning Büttner
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Minyue Qi
- Bioinformatics Core, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | | | - Anna Both
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Martin Christner
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Manuel Wolters
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Malik Alawi
- Bioinformatics Core, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Martin Aepfelbacher
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Holger Rohde
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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3
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Choi GH, Holzapfel WH, Todorov SD. Diversity of the bacteriocins, their classification and potential applications in combat of antibiotic resistant and clinically relevant pathogens. Crit Rev Microbiol 2023; 49:578-597. [PMID: 35731254 DOI: 10.1080/1040841x.2022.2090227] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 04/18/2022] [Accepted: 06/13/2022] [Indexed: 12/19/2022]
Abstract
There is almost a century since discovery of penicillin by Alexander Fleming, a century of enthusiasm, abuse, facing development of antibiotic-resistance and clear conclusion that the modern medicine needs a new type of antimicrobials. Bacteriocins produced by Gram-positive and Gram-negative bacteria, Archaea and Eukaryotes were widely explored as potential antimicrobials with several applications in food industry. In last two decades bacteriocins showed their potential as promising alternative therapeutic for the treatment of antibiotic-resistant pathogens. Bacteriocins can be characterised as highly selective antimicrobials and therapeutics with low cytotoxicity. Most probably in order to solve the problems associated with the increasing number of antibiotic-resistant bacteria, the application of natural or bioengineered bacteriocins in addition to synergistically acting preparations of bacteriocins and conventional antibiotics, can be the next step in combat versus drug-resistant pathogens. In this overview we focussed on diversity of specific lactic acid bacteria and their bacteriocins. Moreover, some additional examples of bacteriocins from non-lactic acid, Gram-positive and Gram-negative bacteria, Archaea and eukaryotic organisms are presented and discussed. Therapeutic properties of bacteriocins, their bioengineering and combined applications, together with conventional antibiotics, were evaluated with the scope of application in human and veterinary medicine for combating (multi-)drug-resistant pathogens.
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Affiliation(s)
- Gee-Hyeun Choi
- ProBacLab, Department of Advanced Convergence, Handong Global University, Pohang, Republic of Korea
| | - Wilhelm Heinrich Holzapfel
- Human Effective Microbes, Department of Advanced Convergence, Handong Global University, Pohang, Republic of Korea
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4
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Yao L, Ding J, Zhang T, Jia Y, Dai J, Zheng X, Yu J, Yang C, Chen X. Heterogeneity changes of active bacterial community on cigar filler leaves after fermentation based on metagenome. Biosci Biotechnol Biochem 2023; 87:1056-1067. [PMID: 37279907 DOI: 10.1093/bbb/zbad071] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/16/2023] [Indexed: 06/08/2023]
Abstract
Microorganisms play an important role in cigar fermentation. To further explore the dynamic changes of bacterial community composition, the changes of surface bacterial diversity of cigar filler leaves were investigated in the present study by high-throughput sequencing technology. It was found that the surface bacterial richness was declined after fermentation, and the dominant microorganisms on the surface of cigar filler leaves evolved from Pseudomonas spp. and Sphingomonas spp. before fermentation to Staphylococcus spp. after fermentation. The chemical composition and sensory quality evaluation of cigar filler leaves were closely related to the changes of surface bacterial community. The changes of the dominant surface bacterial community led to the differences of metabolic functions, among which the metabolic pathways such as the synthesis of secondary metabolites, carbon metabolism, and amino acid biosynthesis were significantly different. The results provide a basis for clarifying the roles of bacteria in fermentation of cigar filler leaves.
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Affiliation(s)
- Lan Yao
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), College of Bioengineering, Hubei University of Technology, 28th of Nanli Road, Wuhan, China
| | - Jingyi Ding
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), College of Bioengineering, Hubei University of Technology, 28th of Nanli Road, Wuhan, China
| | - Tongtong Zhang
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), College of Bioengineering, Hubei University of Technology, 28th of Nanli Road, Wuhan, China
| | - Youpiao Jia
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), College of Bioengineering, Hubei University of Technology, 28th of Nanli Road, Wuhan, China
| | - Jun Dai
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), College of Bioengineering, Hubei University of Technology, 28th of Nanli Road, Wuhan, China
| | - Xueyun Zheng
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), College of Bioengineering, Hubei University of Technology, 28th of Nanli Road, Wuhan, China
| | - Jun Yu
- Tobacco Research Institute of Hubei Province, Wuhan, China
| | - Chunlei Yang
- Tobacco Research Institute of Hubei Province, Wuhan, China
| | - Xiong Chen
- Key Laboratory of Fermentation Engineering (Ministry of Education), Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), College of Bioengineering, Hubei University of Technology, 28th of Nanli Road, Wuhan, China
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5
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Shibasaki S, Ueda M. Utilization of Macroalgae for the Production of Bioactive Compounds and Bioprocesses Using Microbial Biotechnology. Microorganisms 2023; 11:1499. [PMID: 37375001 DOI: 10.3390/microorganisms11061499] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/18/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
To achieve sustainable development, alternative resources should replace conventional resources such as fossil fuels. In marine ecosystems, many macroalgae grow faster than terrestrial plants. Macroalgae are roughly classified as green, red, or brown algae based on their photosynthetic pigments. Brown algae are considered to be a source of physiologically active substances such as polyphenols. Furthermore, some macroalgae can capture approximately 10 times more carbon dioxide from the atmosphere than terrestrial plants. Therefore, they have immense potential for use in the environment. Recently, macroalgae have emerged as a biomass feedstock for bioethanol production owing to their low lignin content and applicability to biorefinery processes. Herein, we provided an overview of the bioconversion of macroalgae into bioactive substances and biofuels using microbial biotechnology, including engineered yeast designed using molecular display technology.
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Affiliation(s)
- Seiji Shibasaki
- Laboratory of Natural Science, Faculty of Economics, Toyo University, Hakusan Bunkyo-ku, Tokyo 112-8606, Japan
| | - Mitsuyoshi Ueda
- Office of Society-Academia Collaboration for Innovation (SACI), Kyoto University, Yoshidahonmachi, Sakyo-ku, Kyoto 606-8501, Japan
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6
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Pimenta LKL, Rodrigues CA, Filho ARG, Coelho CJ, Goes V, Estrela M, de Souza P, Avelino MAG, Vieira JDG, Carneiro L. Staphylococcus spp. Causatives of Infections and Carrier of blaZ, femA, and mecA Genes Associated with Resistance. Antibiotics (Basel) 2023; 12:antibiotics12040671. [PMID: 37107033 PMCID: PMC10135354 DOI: 10.3390/antibiotics12040671] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/15/2023] [Accepted: 03/21/2023] [Indexed: 03/31/2023] Open
Abstract
Staphylococcus spp. have been associated with cases of healthcare associated infections due to their high incidence in isolates from the hospital environment and their ability to cause infections in immunocompromised patients; synthesize biofilms on medical instruments, in the case of negative coagulase species; and change in genetic material, thus making it possible to disseminate genes that code for the acquisition of resistance mechanisms against the action of antibiotics. This study evaluated the presence of blaZ, femA, and mecA chromosomal and plasmid genes of Staphylococcus spp. using the qPCR technique. The results were associated with the phenotypic expression of resistance to oxacillin and penicillin G. We found that the chromosomal femA gene was present in a greater proportion in S. intermedius when compared with the other species analyzed, while the plasmid-borne mecA gene was prevalent in the S. aureus samples. The binary logistic regression performed to verify the association among the expression of the genes analyzed and the acquisition of resistance to oxacillin and penicillin G were not significant in any of the analyses, p > 0.05.
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Affiliation(s)
- Laryssa Ketelyn Lima Pimenta
- Biotechnology Department, Medicine Tropical and Health Public Institute, Universidade Federal de Goiás, Goiania 74605-020, Brazil
| | - Carolina Andrade Rodrigues
- Colemar Natal e Silva Camp, Biotechnology Department, Medicine Faculty, Universidade Federal de Goiás, Goiania 74605-020, Brazil
| | | | - Clarimar José Coelho
- Computer Department, College of Computer Engineering, Pontifíca Universidade Católica de Goiás, Goiania 74605-020, Brazil
| | - Viviane Goes
- Inovation Department, Instituto de Biologia Molecular do Paraná, Curitiba 81350-010, Brazil
| | - Mariely Estrela
- Inovation Department, Instituto de Biologia Molecular do Paraná, Curitiba 81350-010, Brazil
| | - Priscila de Souza
- Inovation Department, Instituto de Biologia Molecular do Paraná, Curitiba 81350-010, Brazil
| | - Melissa Ameloti Gomes Avelino
- Colemar Natal e Silva Camp, Biotechnology Department, Medicine Faculty, Universidade Federal de Goiás, Goiania 74605-020, Brazil
| | - José Daniel Gonçalves Vieira
- Biotechnology Department, Medicine Tropical and Health Public Institute, Universidade Federal de Goiás, Goiania 74605-020, Brazil
| | - Lilian Carneiro
- Biotechnology Department, Medicine Tropical and Health Public Institute, Universidade Federal de Goiás, Goiania 74605-020, Brazil
- Correspondence:
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7
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Mestre Borras A, Dahlsson Leitao C, Ståhl S, Löfblom J. Generation of an anti-idiotypic affibody-based masking domain for conditional activation of EGFR-targeting. N Biotechnol 2023; 73:9-18. [PMID: 36526248 DOI: 10.1016/j.nbt.2022.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 12/07/2022] [Accepted: 12/12/2022] [Indexed: 12/15/2022]
Abstract
Conditional activation of engineered affinity proteins by proteolytic processing is an interesting approach for a wide range of applications. We have generated an anti-idiotypic masking domain with specificity for the binding surface of an EGFR-targeting affibody molecule using an in-house developed staphylococcal display method. The masking domain could specifically abrogate EGFR-binding on cancer cells when fused to the EGFR-targeting affibody molecule via a linker comprising a protease cleavage site. EGFR-binding was restored by proteolytic cleavage of the linker region resulting in release of the masking domain. A saturation mutagenesis study provided detailed information on the interaction between the EGFR-targeting affibody molecule and the masking domain. Introducing an anti-idiotypic masking affibody domain is a viable approach for blocking EGFR-binding and allows for conditional activation by proteolytic processing. The results warrant further studies evaluating the therapeutic and diagnostic applicability both in vitro and in vivo.
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Affiliation(s)
- Anna Mestre Borras
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Charles Dahlsson Leitao
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Stefan Ståhl
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - John Löfblom
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden.
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8
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Dahlsson Leitao C, Mestre Borras A, Jonsson A, Malm M, Kronqvist N, Fleetwood F, Sandersjöö L, Uhlén M, Löfblom J, Ståhl S, Lindberg H. Display of a naïve affibody library on staphylococci for selection of binders by means of flow cytometry sorting. Biochem Biophys Res Commun 2023; 655:75-81. [PMID: 36933310 DOI: 10.1016/j.bbrc.2023.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 03/01/2023] [Indexed: 03/06/2023]
Abstract
Within the field of combinatorial protein engineering there is a great demand for robust high-throughput selection platforms that allow for unbiased protein library display, affinity-based screening, and amplification of selected clones. We have previously described the development of a staphylococcal display system used for displaying both alternative-scaffolds and antibody-derived proteins. In this study, the objective was to generate an improved expression vector for displaying and screening a high-complexity naïve affibody library, and to facilitate downstream validation of isolated clones. A high-affinity normalization tag, consisting of two ABD-moieties, was introduced to simplify off-rate screening procedures. In addition, the vector was furnished with a TEV protease substrate recognition sequence upstream of the protein library which enables proteolytic processing of the displayed construct for improved binding signal. In the library design, 13 of the 58 surface-exposed amino acid positions were selected for full randomization (except proline and cysteine) using trinucleotide technology. The genetic library was successfully transformed to Staphylococcus carnosus cells, generating a protein library exceeding 109 members. De novo selections against three target proteins (CD14, MAPK9 and the affibody ZEGFR:2377) were successfully performed using magnetic bead-based capture followed by flow-cytometric sorting, yielding affibody molecules binding their respective target with nanomolar affinity. Taken together, the results demonstrate the feasibility of the staphylococcal display system and the proposed selection procedure to generate new affibody molecules with high affinity.
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Affiliation(s)
- Charles Dahlsson Leitao
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Anna Mestre Borras
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Andreas Jonsson
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Magdalena Malm
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Nina Kronqvist
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Filippa Fleetwood
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Lisa Sandersjöö
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Mathias Uhlén
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - John Löfblom
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Stefan Ståhl
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Hanna Lindberg
- Department of Protein Science, KTH - Royal Institute of Technology, SE-106 91, Stockholm, Sweden.
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Dahlsson Leitao C, Ståhl S, Löfblom J. Bacterial Cell Display for Selection of Affibody Molecules. Methods Mol Biol 2023; 2681:99-112. [PMID: 37405645 DOI: 10.1007/978-1-0716-3279-6_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/06/2023]
Abstract
This review describes the principles for generation of affibody molecules using bacterial display on the Gram-negative Escherichia coli and the Gram-positive Staphylococcus carnosus, respectively. Affibody molecules are small and robust alternative scaffold proteins that have been explored for therapeutic, diagnostic, and biotechnological applications. They typically exhibit high-stability, affinity, and specificity with high modularity of functional domains. Due to the small size of the scaffold, affibody molecules are rapidly excreted through renal filtration and can efficiently extravasate from blood and penetrate tissues. Preclinical and clinical studies have demonstrated that affibody molecules are promising and safe complements to antibodies for in vivo diagnostic imaging and therapy. Sorting of affibody libraries displayed on bacteria using fluorescence-activated cell sorting is an effective and straightforward methodology and has been used successfully to generate novel affibody molecules with high affinity for a diverse range of molecular targets.
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Affiliation(s)
| | - Stefan Ståhl
- Department of Protein Science, KTH - Royal Institute of Technology, Stockholm, Sweden
| | - John Löfblom
- Department of Protein Science, KTH - Royal Institute of Technology, Stockholm, Sweden.
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Hwang J, Kim Y, Seo Y, Sung M, Oh J, Yoon Y. Effect of Starter Cultures on Quality of Fermented Sausages. Food Sci Anim Resour 2023; 43:1-9. [PMID: 36789202 PMCID: PMC9890365 DOI: 10.5851/kosfa.2022.e75] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 12/22/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022] Open
Abstract
The expansion and advancement of the meat product market have increased the demand for fermented sausages. A typical method for manufacturing high-quality fermented sausages is using a starter culture, which improves the taste, aroma, and texture. Currently, the starter culture for manufacturing fermented sausages is mainly composed of microorganisms such as lactic acid bacteria, yeast, and fungi, which generate volatile compounds by the oxidation of fatty acids. In addition, protein decomposition and changes in pH occur during the fermentation period. It can positively change the texture of the fermented sausage. In this review, we discuss the requirements (improving food safety, the safety of starter culture, enzyme activity, and color) of microorganisms used in starter cultures and the generation of flavor compounds (heptanal, octanal, nonanal, hexanal, 2-pentylfuran, 1-penten-3-ol, and 2-pentanone) from lipids. Furthermore, quality improvement (hardness and chewiness) due to texture changes after starter culture application during the manufacturing process are discussed.
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Affiliation(s)
- Jungeun Hwang
- Department of Food and Nutrition,
Sookmyung Women’s University, Seoul 04310, Korea
| | - Yujin Kim
- Department of Food and Nutrition,
Sookmyung Women’s University, Seoul 04310, Korea
| | - Yeongeun Seo
- Risk Analysis Research Center, Sookmyung
Women’s University, Seoul 04310, Korea
| | - Miseon Sung
- Department of Food and Nutrition,
Sookmyung Women’s University, Seoul 04310, Korea
| | - Jei Oh
- Department of Food and Nutrition,
Sookmyung Women’s University, Seoul 04310, Korea
| | - Yohan Yoon
- Department of Food and Nutrition,
Sookmyung Women’s University, Seoul 04310, Korea,Risk Analysis Research Center, Sookmyung
Women’s University, Seoul 04310, Korea,Corresponding author: Yohan
Yoon, Department of Food and Nutrition, Sookmyung Women’s University,
Seoul 04310, Korea, Tel: +82-2-2077-7585, Fax: +82-2-710-9479,
E-mail:
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11
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Staphylococcal Corneocyte Adhesion: Assay Optimization and Roles of Aap and SasG Adhesins in the Establishment of Healthy Skin Colonization. Microbiol Spectr 2022; 10:e0246922. [PMID: 36219106 PMCID: PMC9769725 DOI: 10.1128/spectrum.02469-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Staphylococcus aureus is an opportunistic pathogen that causes the majority of wound and soft tissue infections. The accumulation-associated protein (Aap) from S. epidermidis and surface protein G (SasG) from S. aureus are cell wall-anchored (CWA) proteins known to be important in adhesion to healthy corneocytes from human skin. We investigated the mechanisms by which S. aureus colonizes healthy human skin by developing an optimized corneocyte adhesion assay. Trypan blue was used for enhanced red autofluorescent visualization of corneocytes with an overlay of green-fluorescent bacteria. The percent area of bacterial adhesion for images acquired by a fluorescence microscope was quantified using Fiji ImageJ. Using this optimized imaging procedure, differences in adhesion between various species and strains of staphylococci were measured. The ability of purified SasG to reduce Staphylococcus epidermidis adhesion was investigated in order to determine if these CWA proteins can compete for binding sites. To further test CWA-mediated adhesion, we engineered a nonadhering S. carnosus strain to express full-length SasG from two methicillin-resistant S. aureus (MRSA) strains. Finally, we demonstrated that the SasG A domain was a critical region of this surface protein for adherence to healthy human corneocytes. The developed imaging and expression methods are useful for studying staphylococcal adhesion to healthy human skin and have the potential to be used with a wide variety of fluorescently labeled organisms on both healthy and disease-state (such as atopic dermatitis) corneocytes. IMPORTANCE The skin is the largest organ of the human body and acts as a shield against hazards such as harmful bacteria like Staphylococcus aureus. A diverse skin microbiota and immune cross talk control S. aureus numbers. S. aureus can bind to healthy skin and subsequently proliferate when the skin barrier is compromised, such as in a wound or in patients with atopic dermatitis (AD). It is important to understand these mechanisms in an effort to prevent pathogenic bacteria from causing infection. We describe an augmented corneocyte adhesion assay using fluorescence microscopy to study binding of various staphylococcal species to healthy human skin cells. In addition, we tested the ability of homologous proteins from different staphylococcal species to reduce binding, and developed a new S. carnosus expression system to test individual protein binding properties. Our newly developed methods and findings will enhance the understanding of how staphylococci bind to healthy human skin.
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12
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Vishwakarma A, Srivastava A, Mishra S, Verma D. Taxonomic and functional profiling of Indian smokeless tobacco bacteriome uncovers several bacterial-derived risks to human health. World J Microbiol Biotechnol 2022; 39:20. [PMID: 36409379 DOI: 10.1007/s11274-022-03461-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 11/07/2022] [Indexed: 11/22/2022]
Abstract
Smokeless tobacco (ST) consumption keeps human oral health at high risk which is one of the major reasons for oral tumorigenesis. The chemical constituents of the ST products have been well discussed; however, the inhabitant microbial diversity of the ST products is less explored especially from south Asian regions. Therefore, the present investigation discusses the bacteriome-based analysis of indigenous tobacco products. The study relies on 16S amplicon-based bacteriome analysis of Indian smokeless tobacco (ST) products using a metagenomic approach. A total of 59,15,143 high-quality reads were assigned to 34 phyla, 82 classes, 176 orders, 256 families, 356 genera, and 154 species using the SILVA database. Of the phyla (> 1%), Firmicutes dominate among the Indian smokeless tobacco followed by Proteobacteria, Bacteroidetes, and Actinobacteria (> 1%). Whereas, at the genera level (> 1%), Lysinibacillus, Dickeya, Terribacillus, and Bacillus dominate. The comparative analysis between the loose tobacco (LT) and commercial tobacco (CT) groups showed no significant difference at the phyla level, however, only three genera (Bacillus, Aerococcus, and Halomonas) were identified as significantly different between the groups. It indicates that CT and LT tobacco share similar bacterial diversity and poses equal health risks to human oral health. The phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt 2.0) based analysis uncovered several genes involved in nitrate/nitrite reduction, biofilm formation, and pro-inflammation that find roles in oral pathogenesis including oral cancer. The strong correlation analysis of these genes with several pathogenic bacteria suggests that tobacco products pose a high bacterial-derived risk to human health. The study paves the way to understand the bacterial diversity of Indian smokeless tobacco products and their putative functions with respect to human oral health. The study grabs attention to the bacterial diversity of the smokeless tobacco products from a country where tobacco consumers are rampantly prevalent however oral health is of least concern.
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Affiliation(s)
- Akanksha Vishwakarma
- Department of Environmental Microbiology, Babasaheb Bhimrao Ambedkar University, Lucknow, 226025, India
| | - Ankita Srivastava
- Department of Environmental Microbiology, Babasaheb Bhimrao Ambedkar University, Lucknow, 226025, India
| | - SukhDev Mishra
- Department of Bio-Statistics and Data Management, ICMR-National Institute of Occupational Health, Ahmedabad, India
| | - Digvijay Verma
- Department of Environmental Microbiology, Babasaheb Bhimrao Ambedkar University, Lucknow, 226025, India.
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13
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Xia C, Zeng X, Peng L, Pan D, Wu Z, Guo Y, Cai Z. The function of uridine diphosphate glucose pyrophosphorylase in the lyophilization-stress response of Lactobacillus acidophilus. ANN MICROBIOL 2022. [DOI: 10.1186/s13213-022-01680-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Purpose
Uridine diphosphate glucose pyrophosphorylase (UGPase) plays an important role in glucose metabolism, catalyzing the reversible formation and decomposition of UDP-glucose (UDPG). In previous work, we found that UGPase is a key enzyme in lyophilization response for Lactobacillus acidophilus (L. acidophilus). However, its function and regulatory mechanism in the freeze-drying stress response are unknown. Herein, the effect of UGPase on freeze-drying survival rate of Staphylococcus carnosus (S. carnosus) was studied.
Methods
In this work, the genes LBA1719 encoding UGPase of L. acidophilus ATCC4356 were inserted into plasmid pMG-36e to construct the recombinant plasmid pMG-LBA1719 and then overexpressed in S. carnosus; the control group was S. carnosus transformed by pMG-36e. The lyophilization-survival rate of overexpressed S. carnosus was determined, and the differentially expressed genes (DEGs) were analyzed by transcriptome to disclose the mechanism of LBA1719 in regulating the lyophilization-survival rate.
Results
Compared with the control group, the UGPase activities of the overexpressed S. carnosus increased by 35.49%, while the lyophilization-survival rates decreased by 11.17% (p < 0.05). Overexpression of LBA1719 decreased the expression of genes gapA, gapB, and pgiA in carbohydrate metabolism and dapA, dapB, and dapE in amino acid metabolism, significantly changing the physiological characteristics of S. carnosus and decreasing its lyophilization-survival rate.
Conclusion
In summary, overexpression of UGPase accelerated the growth rate of S. carnosus and reduced its lyophilization-survival rates. GapA, gapB, pgiA, dapA, dapB, and dapE are vital to lyophilization protection in lactic acid bacteria (LAB). These findings provide new theoretical basis for analyzing the regulatory and molecular mechanisms of lyophilization resistance in LABs.
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Doub JB. Risk of Bacteriophage Therapeutics to Transfer Genetic Material and Contain Contaminants Beyond Endotoxins with Clinically Relevant Mitigation Strategies. Infect Drug Resist 2022; 14:5629-5637. [PMID: 34992389 PMCID: PMC8711558 DOI: 10.2147/idr.s341265] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 12/02/2021] [Indexed: 12/19/2022] Open
Abstract
Bacteriophage therapy is a promising adjuvant therapeutic in the treatment of multidrug-resistant infections and chronic biofilm infections. However, there is limited knowledge about how to best utilize these agents in vivo, leading to a wide range of treatment protocols. Moreover, while bacteriophages are similar to antibiotics in their antimicrobial effects, these are active viruses and are very different from conventional antibiotics. One main difference that clinicians should be cognizant about is the potential ability of these therapeutics to horizontally transfer genetic material, and the clinical ramifications of such events. In addition, while bacteriophage therapeutics are readily tested for sterility and endotoxins, clinicians should also be aware of other contaminants, such as exotoxins, pathogenicity islands and prophages, that can contaminate bacteriophage therapeutics, and their clinical ramifications. While the perception may be that these are only theoretical issues, regulatory agencies are starting to recommend their evaluation when using bacteriophage therapy and subsequently these topics are discussed herein, as are ways to test for and mitigate the adverse effects of these issues.
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Affiliation(s)
- James B Doub
- Division of Clinical Care and Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, USA
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15
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Xiang S, Ye K, Li M, Ying J, Wang H, Han J, Shi L, Xiao J, Shen Y, Feng X, Bao X, Zheng Y, Ge Y, Zhang Y, Liu C, Chen J, Chen Y, Tian S, Zhu X. Xylitol enhances synthesis of propionate in the colon via cross-feeding of gut microbiota. MICROBIOME 2021; 9:62. [PMID: 33736704 PMCID: PMC7977168 DOI: 10.1186/s40168-021-01029-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 02/05/2021] [Indexed: 05/12/2023]
Abstract
BACKGROUND Xylitol, a white or transparent polyol or sugar alcohol, is digestible by colonic microorganisms and promotes the proliferation of beneficial bacteria and the production of short-chain fatty acids (SCFAs), but the mechanism underlying these effects remains unknown. We studied mice fed with 0%, 2% (2.17 g/kg/day), or 5% (5.42 g/kg/day) (weight/weight) xylitol in their chow for 3 months. In addition to the in vivo digestion experiments in mice, 3% (weight/volume) (0.27 g/kg/day for a human being) xylitol was added to a colon simulation system (CDMN) for 7 days. We performed 16S rRNA sequencing, beneficial metabolism biomarker quantification, metabolome, and metatranscriptome analyses to investigate the prebiotic mechanism of xylitol. The representative bacteria related to xylitol digestion were selected for single cultivation and co-culture of two and three bacteria to explore the microbial digestion and utilization of xylitol in media with glucose, xylitol, mixed carbon sources, or no-carbon sources. Besides, the mechanisms underlying the shift in the microbial composition and SCFAs were explored in molecular contexts. RESULTS In both in vivo and in vitro experiments, we found that xylitol did not significantly influence the structure of the gut microbiome. However, it increased all SCFAs, especially propionate in the lumen and butyrate in the mucosa, with a shift in its corresponding bacteria in vitro. Cross-feeding, a relationship in which one organism consumes metabolites excreted by the other, was observed among Lactobacillus reuteri, Bacteroides fragilis, and Escherichia coli in the utilization of xylitol. At the molecular level, we revealed that xylitol dehydrogenase (EC 1.1.1.14), xylulokinase (EC 2.7.1.17), and xylulose phosphate isomerase (EC 5.1.3.1) were key enzymes in xylitol metabolism and were present in Bacteroides and Lachnospiraceae. Therefore, they are considered keystone bacteria in xylitol digestion. Also, xylitol affected the metabolic pathway of propionate, significantly promoting the transcription of phosphate acetyltransferase (EC 2.3.1.8) in Bifidobacterium and increasing the production of propionate. CONCLUSIONS Our results revealed that those key enzymes for xylitol digestion from different bacteria can together support the growth of micro-ecology, but they also enhanced the concentration of propionate, which lowered pH to restrict relative amounts of Escherichia and Staphylococcus. Based on the cross-feeding and competition among those bacteria, xylitol can dynamically balance proportions of the gut microbiome to promote enzymes related to xylitol metabolism and SCFAs. Video Abstract.
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Affiliation(s)
- Shasha Xiang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Kun Ye
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Mian Li
- Zhejiang Huakang Pharmaceutical Co., Ltd., Kaihua, 324302 China
| | - Jian Ying
- Nutrition and Health Research Institute, COFCO Ltd., Beijing, 102209 China
| | - Huanhuan Wang
- School of Medicine, Hangzhou Normal University, Hangzhou, 310018 China
- Laboratory of Aging and Cancer Biology of Zhejiang Province, Hangzhou Normal University, Hangzhou, 311121 China
| | - Jianzhong Han
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Lihua Shi
- Zhejiang Huakang Pharmaceutical Co., Ltd., Kaihua, 324302 China
| | - Jie Xiao
- Nutrition and Health Research Institute, COFCO Ltd., Beijing, 102209 China
| | - Yubiao Shen
- Yangtze Delta Institute of Tsinghua University, Jiaxing, 314000 China
| | - Xiao Feng
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Xuan Bao
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Yiqing Zheng
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Yin Ge
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Yalin Zhang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Chang Liu
- School of Food Science and Technology, Jiangnan University, Wuxi, 214122 China
| | - Jie Chen
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Yuewen Chen
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Shiyi Tian
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
| | - Xuan Zhu
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018 China
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16
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Nicchi S, Giuliani M, Giusti F, Pancotto L, Maione D, Delany I, Galeotti CL, Brettoni C. Decorating the surface of Escherichia coli with bacterial lipoproteins: a comparative analysis of different display systems. Microb Cell Fact 2021; 20:33. [PMID: 33531008 PMCID: PMC7853708 DOI: 10.1186/s12934-021-01528-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 01/23/2021] [Indexed: 11/10/2022] Open
Abstract
Background The display of recombinant proteins on cell surfaces has a plethora of applications including vaccine development, screening of peptide libraries, whole-cell biocatalysts and biosensor development for diagnostic, industrial or environmental purposes. In the last decades, a wide variety of surface display systems have been developed for the exposure of recombinant proteins on the surface of Escherichia coli, such as autotransporters and outer membrane proteins. Results In this study, we assess three approaches for the surface display of a panel of heterologous and homologous mature lipoproteins in E. coli: four from Neisseria meningitidis and four from the host strain that are known to be localised in the inner leaflet of the outer membrane. Constructs were made carrying the sequences coding for eight mature lipoproteins, each fused to the delivery portion of three different systems: the autotransporter adhesin involved in diffuse adherence-I (AIDA-I) from enteropathogenic E. coli, the Lpp’OmpA chimaera and a truncated form of the ice nucleation protein (INP), InaK-NC (N-terminal domain fused with C-terminal one) from Pseudomonas syringae. In contrast to what was observed for the INP constructs, when fused to the AIDA-I or Lpp’OmpA, most of the mature lipoproteins were displayed on the bacterial surface both at 37 and 25 °C as demonstrated by FACS analysis, confocal and transmission electron microscopy. Conclusions To our knowledge this is the first study that compares surface display systems using a number of passenger proteins. We have shown that the experimental conditions, including the choice of the carrier protein and the growth temperature, play an important role in the translocation of mature lipoproteins onto the bacterial surface. Despite all the optimization steps performed with the InaK-NC anchor motif, surface exposure of the passenger proteins used in this study was not achieved. For our experimental conditions, Lpp’OmpA chimaera has proved to be an efficient surface display system for the homologous passenger proteins although cell lysis and phenotype heterogeneity were observed. Finally, AIDA-I was found to be the best surface display system for mature lipoproteins (especially heterologous ones) in the E. coli host strain with no inhibition of growth and only limited phenotype heterogeneity.
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Affiliation(s)
- Sonia Nicchi
- GSK, via Fiorentina 1, 53100, Siena, Italy.,Department of Pharmacy and Biotechnology (FaBiT), University of Bologna, Bologna, Italy
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17
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The Use of the Mixed Bacteria Limosilactobacillus fermentum and Staphylococcus carnosus in the Meat Curing Process with a Reduced Amount of Sodium Nitrite. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11030904] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The aim of the research was to estimate the possibility of using mixed bacteria cultures consisting of Lactobacillus fermentum S8 and Staphylococcus carnosus ATCC 51365 in the meat curing process with a reduced amount of sodium nitrite and to study the effect of bacteria on residual nitrites and nitrates, nitrosyl pigments content, colour, pH, redox potential, microbiologic, and the sensory quality of a cooked meat product. The study was performed on heat treated three-model meat treatments in cans: (C) a control treatment with NaNO2 at 100 mg/kg, (M) a treatment with NaNO2 at 50 mg/kg and (SL) a treatment with NaNO2 at 50 mg/kg and L. fermentum S8 at about 107 cfu/g and S. carnosus ATCC 51365 at about of 107 cfu/g. The research was performed after production and after cold storage. It was shown that using a mixed bacteria culture for meat curing had an influence (p < 0.05) on reducing nitrite and nitrate levels and increasing the amount of nitrosyl pigments in the SL treatment compared to the M treatment. Applying mixed bacteria in curing meat with NaNO2 at 50 mg/kg allowed for obtaining a higher redness in the cooked meat product after production, storage and exposure to light than in the product cured with NaNO2 at 100 mg/kg, with similar sensory and microbiological quality in both products.
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18
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Rodpai R, Sanpool O, Thanchomnang T, Wangwiwatsin A, Sadaow L, Phupiewkham W, Boonroumkaew P, Intapan PM, Maleewong W. Investigating the microbiota of fermented fish products (Pla-ra) from different communities of northeastern Thailand. PLoS One 2021; 16:e0245227. [PMID: 33444386 PMCID: PMC7808594 DOI: 10.1371/journal.pone.0245227] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 12/27/2020] [Indexed: 11/21/2022] Open
Abstract
DNA-sequencing was performed on the V3-V4 regions of 16S rRNA genes to investigate the microbial diversity of five samples of fermented freshwater fish (pla-ra) from three provinces in northeastern Thailand. The samples had salt concentrations ranging from 7 to 10%, pH values from 4.83 to 7.15, and D-/L-lactic acid concentrations of 90 to 450 mg/l. A total of 598 operational taxonomic units were annotated at various taxonomic ranks based on the SILVA Database. The lactic-acid and halophilic genera Tetragenococcus, Halanaerobium and Lactobacillus were among the dominant taxa of bacteria. The top 20 non-redundant taxa were considered in more detail. In two pla-ra samples, Tetragenococcus muriaticus was commonly identified. Halanaerobium fermentans was the most abundant species in a third sample and co-dominant in another sample. Lactobacillus rennini was dominant in the pla-ra sample from Roi Et Province. Additionally, other beneficial bacteria were detected including Staphylococcus nepalensis, Lactobacillus sakei, Lactobacillus pentosus, Weissella confusa, and Bifidobacterium bifidum. Differences between samples may be due to use of different raw materials, salt concentrations, recipes, processes and fermentation periods. The microbial communities in pla-ra provide a better understanding of the production outcomes of traditional products. Further optimization of the fermentation process, for example by using dominant bacterial taxa in starter cultures, may improve processes of food fermentation, food quality and flavor control, providing useful guidelines for industrial applications.
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Affiliation(s)
- Rutchanee Rodpai
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Faculty of Medicine, Khon Kaen, Thailand
| | - Oranuch Sanpool
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Faculty of Medicine, Khon Kaen, Thailand
| | - Tongjit Thanchomnang
- Mekong Health Science Research Institute, Faculty of Medicine, Khon Kaen, Thailand
- Faculty of Medicine, Mahasarakram University, Mahasarakram, Thailand
| | - Arporn Wangwiwatsin
- Department of Biology, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
| | - Lakkhana Sadaow
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Faculty of Medicine, Khon Kaen, Thailand
| | - Weeraya Phupiewkham
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Faculty of Medicine, Khon Kaen, Thailand
| | - Patcharaporn Boonroumkaew
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Faculty of Medicine, Khon Kaen, Thailand
| | - Pewpan M Intapan
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Faculty of Medicine, Khon Kaen, Thailand
| | - Wanchai Maleewong
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Faculty of Medicine, Khon Kaen, Thailand
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19
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Strategies to Improve Meat Products' Quality. Foods 2020; 9:foods9121883. [PMID: 33348725 PMCID: PMC7766022 DOI: 10.3390/foods9121883] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/08/2020] [Accepted: 12/16/2020] [Indexed: 02/07/2023] Open
Abstract
Meat products represent an important component of the human diet, their consumption registering a global increase over the last few years. These foodstuffs constitute a good source of energy and some nutrients, such as essential amino acids, high biological value proteins, minerals like iron, zinc, selenium, manganese and B-complex vitamins, especially vitamin B12. On the other hand, nutritionists have associated high consumption of processed meat with an increased risk of several diseases. Researchers and processed meat producers are involved in finding methods to eliminate nutritional deficiencies and potentially toxic compounds, to obtain healthier products and at the same time with no affecting the sensorial quality and safety of the meat products. The present review aims to summarize the newest trends regarding the most important methods that can be applied to obtain high-quality products. Nutritional enrichment with natural bioactive plant compounds (antioxidants, dietary fibers) or probiotics, reduction of harmful components (salt, nitrate/nitrite, N-nitrosamines) and the use of alternative technologies (high-pressure processing, cold plasma, ultrasounds) are the most used current strategies to accomplish this aim.
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Abstract
The concept of engineering robust protein scaffolds for novel binding functions emerged 20 years ago, one decade after the advent of recombinant antibody technology. Early examples were the Affibody, Monobody (Adnectin), and Anticalin proteins, which were derived from fragments of streptococcal protein A, from the tenth type III domain of human fibronectin, and from natural lipocalin proteins, respectively. Since then, this concept has expanded considerably, including many other protein templates. In fact, engineered protein scaffolds with useful binding specificities, mostly directed against targets of biomedical relevance, constitute an area of active research today, which has yielded versatile reagents as laboratory tools. However, despite strong interest from basic science, only a handful of those protein scaffolds have undergone biopharmaceutical development up to the clinical stage. This includes the abovementioned pioneering examples as well as designed ankyrin repeat proteins (DARPins). Here we review the current state and clinical validation of these next-generation therapeutics.
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Affiliation(s)
| | - Arne Skerra
- Lehrstuhl für Biologische Chemie, Technische Universität München, 85354 Freising, Germany;
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21
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Güler R, Svedmark SF, Abouzayed A, Orlova A, Löfblom J. Increasing thermal stability and improving biodistribution of VEGFR2-binding affibody molecules by a combination of in silico and directed evolution approaches. Sci Rep 2020; 10:18148. [PMID: 33097752 PMCID: PMC7585445 DOI: 10.1038/s41598-020-74560-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/23/2020] [Indexed: 11/09/2022] Open
Abstract
The family of vascular endothelial growth factor (VEGF) ligands and their interactions with VEGF receptors (VEGFRs) play important roles in both pathological and physiological angiogenesis. Hence, agonistic and antagonistic ligands targeting this signaling pathway have potential for both studies on fundamental biology and for development of therapies and diagnostics. Here, we engineer VEGFR2-binding affibody molecules for increased thermostability, refolding and improved biodistribution. We designed libraries based on the original monomeric binders with the intention of reducing hydrophobicity, while retaining high affinity for VEGFR2. Libraries were displayed on bacteria and binders were isolated by fluorescence-activated cell sorting (FACS). In parallel, we used an automated sequence- and structure-based in silico algorithm to identify potentially stabilizing mutations. Monomeric variants isolated from the screening and the in silico approach, respectively, were characterized by circular dichroism spectroscopy and biosensor assays. The most promising mutations were combined into new monomeric constructs which were finally fused into a dimeric construct, resulting in a 15 °C increase in melting temperature, complete refolding capability after heat-induced denaturation, retained low picomolar affinity and improved biodistribution profile in an in vivo mouse model. These VEGFR2-binding affibody molecules show promise as candidates for further in vivo studies to assess their suitability as molecular imaging and therapeutic agents.
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Affiliation(s)
- Rezan Güler
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Siri Flemming Svedmark
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Ayman Abouzayed
- Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
| | - Anna Orlova
- Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
- Science for Life Laboratory, Uppsala University, Uppsala, Sweden
- Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, Tomsk, Russia
| | - John Löfblom
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden.
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22
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Wang Y, Li F, Chen J, Sun Z, Wang F, Wang C, Fu L. High-throughput sequencing-based characterization of the predominant microbial community associated with characteristic flavor formation in Jinhua Ham. Food Microbiol 2020; 94:103643. [PMID: 33279069 DOI: 10.1016/j.fm.2020.103643] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 09/11/2020] [Accepted: 09/13/2020] [Indexed: 01/10/2023]
Abstract
Our purpose was to investigate the main bacterial microbiota and volatile profiles in the Chinese traditional dry-cured product-Jinhua ham during different processing stages and to analyze the role of the main microbiota in the formation of characteristic flavor. We determined the microbiota of Jinhua ham by using 16 S high throughput sequencing, and found that Staphylococcus constituted the predominant microbiota throughout the flavor formation process. Based on the volatile profiles of Jinhua dry-cured products from 11 different processing via SPME-GC-MS analysis, Aldehydes were the main groups of volatiles, with the most abundant ones being hexanal (13.89%) and nonanal (3.96%). To further investigate the relationship between predominant microbiota and the major volatile compounds in Jinhua ham, we screened and isolated genus Staphylococcus with high protease and lipase activities. The main Staphylococcus isolates, S. saprophyticus (53.4%) and S. equorum (31.0%) are related to the yields of aldehydes by producing hexanal, nonanal, benzaldehyde, and phenylacetaldehyde, indicating their contributions on the formation of characteristic flavor substances in Jinhua ham.
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Affiliation(s)
- Yanbo Wang
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, PR China
| | - Fan Li
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, PR China
| | - Jian Chen
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, PR China
| | - Zhihua Sun
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, PR China
| | - Feifei Wang
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, PR China
| | - Chong Wang
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, PR China
| | - Linglin Fu
- Food Safety Key Laboratory of Zhejiang Province, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, PR China.
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Ozaki MM, Munekata PES, Jacinto-Valderrama RA, Efraim P, Pateiro M, Lorenzo JM, Pollonio MAR. Beetroot and radish powders as natural nitrite source for fermented dry sausages. Meat Sci 2020; 171:108275. [PMID: 32853888 DOI: 10.1016/j.meatsci.2020.108275] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/27/2020] [Accepted: 08/07/2020] [Indexed: 02/08/2023]
Abstract
The aim of this study was to investigate the use of radish and beetroot powders as potential substitutes of nitrite in fermented dry sausages due to their high nitrate content (around 16,000 and 14,000 mg/kg, respectively). Six treatments were prepared and evaluated during the ripening process and storage time: C1 (control with 150 mg/kg sodium nitrite and 150 mg/kg sodium nitrate), C2 (control without sodium nitrite/nitrate), R05 (0.5% radish powder), R1 (1% radish powder), B05 (0.5% beetroot powder) and B1 (1% beetroot powder). The addition of vegetable powders influenced moisture content, weight loss and water activity of sausages. Nitrite was formed from radish and beetroot powders during the ripening process, especially in R1 and B1 treatments. Beetroot powder affected colour, pigments and lactic acid bacteria counts. The results of pH, colour, lipid oxidation, nitrite and nitrate analysis suggest R1 treatment as a potential nitrite replacer obtained from a simple and feasible drying process.
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Affiliation(s)
- Maristela Midori Ozaki
- Department of Food Technology, School of Food Engineering, State University of Campinas (Unicamp), 13083-862 Campinas, SP, Brazil
| | - Paulo E S Munekata
- Centro Tecnológico de la Carne de Galicia, Rúa Galicia N° 4, Parque Tecnológico de Galicia, San Cibrao das Viñas, 32900 Ourense, Spain
| | | | - Priscilla Efraim
- Department of Food Technology, School of Food Engineering, State University of Campinas (Unicamp), 13083-862 Campinas, SP, Brazil
| | - Mirian Pateiro
- Centro Tecnológico de la Carne de Galicia, Rúa Galicia N° 4, Parque Tecnológico de Galicia, San Cibrao das Viñas, 32900 Ourense, Spain
| | - José Manuel Lorenzo
- Centro Tecnológico de la Carne de Galicia, Rúa Galicia N° 4, Parque Tecnológico de Galicia, San Cibrao das Viñas, 32900 Ourense, Spain; Área de Tecnología de los Alimentos, Facultad de Ciencias de Ourense, Universidad de Vigo, 32004 Ourense, Spain
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Heo S, Lee JH, Jeong DW. Food-derived coagulase-negative Staphylococcus as starter cultures for fermented foods. Food Sci Biotechnol 2020; 29:1023-1035. [PMID: 32670656 PMCID: PMC7347722 DOI: 10.1007/s10068-020-00789-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 06/15/2020] [Accepted: 06/18/2020] [Indexed: 02/07/2023] Open
Abstract
Food safety is of significant concern to consumers and is a major issue for the food industry. As such, the industry is aware of the importance of safety assessments of starters used in the production of fermented foods. Coagulase-negative staphylococci (CNS) are the predominant bacteria found in fermented foods worldwide. Because of this, food-derived CNS are used as starters for cheese and meat fermentation, and have been investigated for use as starters in soybean fermentation. Although food-derived CNS are generally considered non-pathogenic, their safety remains uncertain following the isolation of CNS from skin infections in humans and animals, and because they belong to the same genus as the highly pathogenic species Staphylococcus aureus. This review explores what is known about the safety of food-derived CNS, focusing on antibiotic resistance, enterotoxin genes, and biogenic amine production, to aid in the selection of starter candidates.
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Affiliation(s)
- Sojeong Heo
- Department of Food and Nutrition, Dongduk Women’s University, Seoul, Republic of Korea
| | - Jong-Hoon Lee
- Department of Food Science and Biotechnology, Kyonggi University, Suwon, Republic of Korea
| | - Do-Won Jeong
- Department of Food and Nutrition, Dongduk Women’s University, Seoul, Republic of Korea
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25
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Treffon J, Fotiadis SA, van Alen S, Becker K, Kahl BC. The Virulence Potential of Livestock-Associated Methicillin-Resistant Staphylococcus aureus Cultured from the Airways of Cystic Fibrosis Patients. Toxins (Basel) 2020; 12:E360. [PMID: 32486247 PMCID: PMC7354617 DOI: 10.3390/toxins12060360] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 05/20/2020] [Accepted: 05/27/2020] [Indexed: 01/25/2023] Open
Abstract
Staphylococcus aureus is one of the most common pathogens that infects the airways of patients with cystic fibrosis (CF) and contributes to respiratory failure. Recently, livestock-associated methicillin-resistant S. aureus (LA-MRSA), usually cultured in farm animals, were detected in CF airways. Although some of these strains are able to establish severe infections in humans, there is limited knowledge about the role of LA-MRSA virulence in CF lung disease. To address this issue, we analyzed LA-MRSA, hospital-associated (HA-) MRSA and methicillin-susceptible S.aureus (MSSA) clinical isolates recovered early in the course of airway infection and several years after persistence in this hostile environment from pulmonary specimens of nine CF patients regarding important virulence traits such as their hemolytic activity, biofilm formation, invasion in airway epithelial cells, cytotoxicity, and antibiotic susceptibility. We detected that CF LA-MRSA isolates were resistant to tetracycline, more hemolytic and cytotoxic than HA-MRSA, and more invasive than MSSA. Despite the residence in the animal host, LA-MRSA still represent a serious threat to humans, as such clones possess a virulence potential similar or even higher than that of HA-MRSA. Furthermore, we confirmed that S. aureus individually adapts to the airways of CF patients, which eventually impedes the success of antistaphylococcal therapy of airway infections in CF.
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Affiliation(s)
- Janina Treffon
- Institute of Medical Microbiology, University Hospital Münster, 48149 Münster, Germany; (J.T.); (S.A.F.); (S.v.A.); (K.B.)
- Institute of Hygiene, University Hospital Münster, 48149 Münster, Germany
| | - Sarah Ann Fotiadis
- Institute of Medical Microbiology, University Hospital Münster, 48149 Münster, Germany; (J.T.); (S.A.F.); (S.v.A.); (K.B.)
| | - Sarah van Alen
- Institute of Medical Microbiology, University Hospital Münster, 48149 Münster, Germany; (J.T.); (S.A.F.); (S.v.A.); (K.B.)
- Business Unit Pain, Grünenthal GmbH, 52222 Stolberg, Germany
| | - Karsten Becker
- Institute of Medical Microbiology, University Hospital Münster, 48149 Münster, Germany; (J.T.); (S.A.F.); (S.v.A.); (K.B.)
- Friedrich Loeffler-Institute of Medical Microbiology, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Barbara C. Kahl
- Institute of Medical Microbiology, University Hospital Münster, 48149 Münster, Germany; (J.T.); (S.A.F.); (S.v.A.); (K.B.)
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26
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Effects of the Use of Staphylococcus carnosus in the Curing Process of Meat with a Reduced Amount of Sodium Nitrite on Colour, Residue Nitrite and Nitrate, Content of Nitrosyl Pigments, and Microbiological and the Sensory Quality of Cooked Meat Product. J FOOD QUALITY 2020. [DOI: 10.1155/2020/6141728] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The aim of the work was to apply the bacteria Staphylococcus carnosus ATCC 51365 in the meat curing process with the use of a reduced amount of sodium nitrite and to evaluate the effects of bacteria on residual nitrites and nitrates, the content of nitrosyl pigments, colour, pH, oxidation-reduction potential, microbiological, and the sensory quality of a cooked meat product. Three meat batters in cans were prepared: (C) a control batter cured with NaNO2—100 mg/kg, (L) a batter cured with NaNO2—15 mg/kg, and (LS) a batter cured with NaNO2—15 mg/kg and S. carnosus (107 CFU/g). The cans were stored at a temperature of 4°C for 24 h (curing time) and cooked. The analysis was carried out after production and after 4 and 8 weeks of storage. The use of denitrifying bacteria in the curing process with a reduced amount of sodium nitrite increased the availability of nitrite in the meat, by reducing nitrates formed as a result of a dismutation reaction. The reaction contributed to the formation of nitrosyl pigments in a larger quantity than in the treatment in which the denitrifying bacteria were not used. The LS treatment was characterized by the greatest redness. The colour of the LS treatment was stable during storage. No negative effect of S. carnosus on the sensory quality of the meat product was found. The use of S. carnosus had no influence on the microbiological quality of meat product during storage.
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27
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Hoenes K, Wenzel U, Spellerberg B, Hessling M. Photoinactivation Sensitivity of
Staphylococcus carnosus
to Visible‐light Irradiation as a Function of Wavelength. Photochem Photobiol 2019; 96:156-169. [DOI: 10.1111/php.13168] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 09/16/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Katharina Hoenes
- Institute of Medical Engineering and Mechatronics Ulm University of Applied Sciences Ulm Germany
| | - Ulla Wenzel
- Institute of Medical Engineering and Mechatronics Ulm University of Applied Sciences Ulm Germany
| | | | - Martin Hessling
- Institute of Medical Engineering and Mechatronics Ulm University of Applied Sciences Ulm Germany
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28
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Maldonado SL, Krull J, Rasch D, Panjan P, Sesay AM, Marques MPC, Szita N, Krull R. Application of a multiphase microreactor chemostat for the determination of reaction kinetics of Staphylococcus carnosus. Bioprocess Biosyst Eng 2019; 42:953-961. [PMID: 30810809 DOI: 10.1007/s00449-019-02095-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 02/17/2019] [Indexed: 10/27/2022]
Abstract
Bioreactors at the microliter scale offer a promising approach to accelerate bioprocess development. Advantages of such microbioreactors include a reduction in the use of expensive reagents. In this study, a chemostat operation mode of a cuvette-based microbubble column bioreactor made of polystyrene (working volume of 550 µL) was demonstrated. Aeration occurs through a nozzle (Ø ≤ 100 µm) and supports submerged whole-cell cultivation of Staphylococcus carnosus. Stationary concentrations of biomass and glucose were determined in the dilution rate regime ranging from 0.12 to 0.80 1/h with a glucose feed concentration of 1 g/L. For the first time, reaction kinetics of S. carnosus were estimated from data obtained from continuous cultivation. The maximal specific growth rate (µmax = 0.824 1/h), Monod constant (KS = 34 × 10- 3gS/L), substrate-related biomass yield coefficient (YX/S = 0.315 gCDW/gS), and maintenance coefficient (mS = 0.0035 gS/(gCDW·h)) were determined. These parameters are now available for further studies in the field of synthetic biology.
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Affiliation(s)
- S Lladó Maldonado
- Institute of Biochemical Engineering, Technische Universität Braunschweig, Rebenring 56, 38106, Braunschweig, Germany.,Center of Pharmaceutical Engineering (PVZ), Technische Universität Braunschweig, Braunschweig, Germany
| | - J Krull
- Institute of Biochemical Engineering, Technische Universität Braunschweig, Rebenring 56, 38106, Braunschweig, Germany.,Center of Pharmaceutical Engineering (PVZ), Technische Universität Braunschweig, Braunschweig, Germany
| | - D Rasch
- Institute of Biochemical Engineering, Technische Universität Braunschweig, Rebenring 56, 38106, Braunschweig, Germany.,Center of Pharmaceutical Engineering (PVZ), Technische Universität Braunschweig, Braunschweig, Germany
| | - P Panjan
- Measurement Technology Unit, CEMIS-Oulu, Kajaani University Consortium, University of Oulu, Kajaani, Finland
| | - A M Sesay
- Measurement Technology Unit, CEMIS-Oulu, Kajaani University Consortium, University of Oulu, Kajaani, Finland
| | - M P C Marques
- Department of Biochemical Engineering, University College London, London, UK
| | - N Szita
- Department of Biochemical Engineering, University College London, London, UK
| | - R Krull
- Institute of Biochemical Engineering, Technische Universität Braunschweig, Rebenring 56, 38106, Braunschweig, Germany. .,Center of Pharmaceutical Engineering (PVZ), Technische Universität Braunschweig, Braunschweig, Germany.
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29
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Bierowiec K, Korzeniowska-Kowal A, Wzorek A, Rypuła K, Gamian A. Prevalence of Staphylococcus Species Colonization in Healthy and Sick Cats. BIOMED RESEARCH INTERNATIONAL 2019; 2019:4360525. [PMID: 30800668 PMCID: PMC6360576 DOI: 10.1155/2019/4360525] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 12/29/2018] [Accepted: 01/03/2019] [Indexed: 11/17/2022]
Abstract
Staphylococcus is one of the most frequently isolated genera of opportunistic bacteria in animals and human beings. Staphylococci in mammals mostly inhabit the skin and mucous membranes. The objectives of the study were to investigate the distribution of staphylococcal species in healthy and sick cats in order to find diagnostic markers. The risk factors associated with colonization were also explored. Isolates from healthy (n=520) and sick cats (n=67) were identified at the species level using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). Swabs from conjunctival sacs, nares, skin, anus, and wounds were investigated using this technique. The diversity of the Staphylococcus species was high: 26 and 17 species in healthy and sick cats, respectively, and predominantly coagulase-negative staphylococci (CoNS) were isolated. The most frequently observed were S. felis and S. epidermidis in healthy cats, whereas S. felis and S. haemolyticus were most often found in sick animals. S. aureus strains were only isolated from healthy cats, whereas the only coagulase-positive Staphylococcus (CoPS) which occurred in the sick cats group was S. pseudintermedius. The sick, more frequently than the healthy animals, were colonized with S. pseudintermedius and S. haemolyticus and the relationship was statistically significant. Mostly, regardless of the state of their health, similar Staphylococcus species were isolated from cats; therefore, particular attention should be paid during the interpretation of diagnostic results.
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Affiliation(s)
- K. Bierowiec
- Division of Infectious Diseases and Veterinary Administration, Department of Epizootiology and Clinic of Birds and Exotic Animals, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, 50-366 Wroclaw, Poland
| | - A. Korzeniowska-Kowal
- Department of Immunology of Infectious Diseases, Hirszfeld Institute of Immunology and Experimental Therapy, 53-114 Wroclaw, Poland
| | - A. Wzorek
- Department of Immunology of Infectious Diseases, Hirszfeld Institute of Immunology and Experimental Therapy, 53-114 Wroclaw, Poland
| | - K. Rypuła
- Division of Infectious Diseases and Veterinary Administration, Department of Epizootiology and Clinic of Birds and Exotic Animals, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, 50-366 Wroclaw, Poland
| | - A. Gamian
- Department of Immunology of Infectious Diseases, Hirszfeld Institute of Immunology and Experimental Therapy, 53-114 Wroclaw, Poland
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30
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Divyakolu S, Chikkala R, Ratnakar KS, Sritharan V. Hemolysins of <i>Staphylococcus aureus</i>—An Update on Their Biology, Role in Pathogenesis and as Targets for Anti-Virulence Therapy. ACTA ACUST UNITED AC 2019. [DOI: 10.4236/aid.2019.92007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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31
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Andersson KG, Persson J, Ståhl S, Löfblom J. Autotransporter-Mediated Display of a Naïve Affibody Library on the Outer Membrane of Escherichia coli. Biotechnol J 2018; 14:e1800359. [PMID: 30179307 DOI: 10.1002/biot.201800359] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/23/2018] [Indexed: 12/14/2022]
Abstract
Development of new affinity proteins using combinatorial protein engineering is today established for generation of monoclonal antibodies and also essential for discovery of binders that are based on non-immunoglobulin proteins. Phage display is most frequently used, but yeast display is becoming increasingly popular, partly due to the option of utilizing fluorescence-activated cell sorting (FACS) for isolation of new candidates. Escherichia coli has several valuable properties for library applications and in particular the high transformation efficiency. The use of various autotransporters and intimins for secretion and anchoring on the outer membrane have shown promising results and particularly for directed evolution of different enzymes. Here, the authors report on display of a large naïve affibody library on the outer membrane of E. coli using the autotransporter Adhesin Involved in Diffuse Adherence (AIDA-I). The expression cassette is first engineered by removing non-essential sequences, followed by introduction of an affibody library, comprising more than 109 variants, into the new display vector. The quality of the library and general performance of the method is assessed by FACS against five different targets, which resulted in a panel of binders with down to nanomolar affinities, suggesting that the method has potential as a complement to phage display for generation of affibody molecules.
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Affiliation(s)
- Ken G Andersson
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Jonas Persson
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - Stefan Ståhl
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, SE-106 91, Stockholm, Sweden
| | - John Löfblom
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, SE-106 91, Stockholm, Sweden
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