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Thakur R, Shishodia SK, Sharma A, Chauhan A, Kaur S, Shankar J. Accelerating the understanding of Aspergillus terreus: Epidemiology, physiology, immunology and advances. CURRENT RESEARCH IN MICROBIAL SCIENCES 2024; 6:100220. [PMID: 38303967 PMCID: PMC10831165 DOI: 10.1016/j.crmicr.2024.100220] [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] [Indexed: 02/03/2024] Open
Abstract
Aspergillus species encompass a variety of infections, ranging from invasive aspergillosis to allergic conditions, contingent upon the immune status of the host. In this spectrum, Aspergillus terreus stands out due to its emergence as a notable pathogen and its intrinsic resistance to amphotericin-B. The significance of Aspergillus-associated infections has witnessed a marked increase in the past few decades, particularly with the increasing number of immunocompromised individuals. The exploration of epidemiology, morphological transitions, immunopathology, and novel treatment approaches such as new antifungal drugs (PC945, olorofim) and combinational therapy using antifungal drugs and phytochemicals (Phytochemicals: quercetin, shikonin, artemisinin), also using immunotherapies to modulate immune response has resulted in better outcomes. Furthermore, in the context COVID-19 era and its aftermath, fungal infections have emerged as a substantial challenge for both immunocompromised and immunocompetent individuals. This is attributed to the use of immune-suppressing therapies during COVID-19 infections and the increase in transplant cases. Consequently, this review aims to provide an updated overview encompassing the epidemiology, germination events, immunopathology, and novel drug treatment strategies against Aspergillus terreus-associated infections.
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Affiliation(s)
- Raman Thakur
- Department of Medical Laboratory Science, Lovely Professional University, Jalandhar, Punjab, India
| | | | - Ananya Sharma
- Genomic Laboratory, Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat Solan, Himachal Pradesh, India
| | - Arjun Chauhan
- Department of Biotechnology, Institute of Applied Sciences and Humanities, GLA University, Mathura, Uttar Pradesh, India
| | - Sumanpreet Kaur
- Department of Medical Laboratory Science, Lovely Professional University, Jalandhar, Punjab, India
| | - Jata Shankar
- Genomic Laboratory, Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat Solan, Himachal Pradesh, India
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Chatterjee S, Das S. Whole-genome sequencing of biofilm-forming and chromium-resistant mangrove fungus Aspergillus niger BSC-1. World J Microbiol Biotechnol 2022; 39:55. [PMID: 36565384 DOI: 10.1007/s11274-022-03497-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/13/2022] [Indexed: 12/25/2022]
Abstract
Filamentous fungus Aspergillus niger has gained significant industrial and ecological value due to its great potential in enzymatic activities. The present study reports the complete genome sequence of A. niger BSC-1 which was isolated from Indian Sundarban mangrove ecosystem. The study revealed that the genome of A. niger BSC-1 was 35.1 Mbp assembled in 40 scaffolds with 49.2% GC content. A total of 10,709 genes were reported out of which 10,535 genes were predicted for encoding the proteins. BUSCO assessment showed 98.6% of genome completeness indicating high quality genome sequencing. The genome sequencing of A. niger BSC-1 revealed the presence of rodA and exgA genes for initial adhesion to surface and Ags genes for matrix formation, during biofilm growth. OrthoVenn2 analysis revealed that A.niger BSC-1 shared 9552 gene clusters with the reference strain A. niger CBS554.65. Semi-quantitative RT-PCR analysis unveiled the role of Ags1 and P-type ATPase in fungal biofilm formation and chromium (Cr) resistance, respectively. During biofilm growth the expression of Ags1 significantly (P < 0.0001; two-way ANOVA followed by Sidak's multiple comparisons test) increased with respect to planktonic culture revealing the possible involvement of Ags1 in biofilm matrix formation. Expression of P-type ATPase gene was significantly upregulated (P < 0.0001; one-way ANOVA followed by Dunnett's multiple comparisons test) with the increasing chromium concentration in the fungal culture. Besides, several other genes encoding metalloprotease, copper and zinc binding proteins, and NADH-dependent oxidoreductase were also found in the genome of A. niger BSC-1. These proteins are also involved in heavy metal tolerance and nanofabrication indicating that this filamentous fungus A. niger BSC-1 could be potentially utilized for chromium detoxification through biofilm or nanobiremediation.
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Affiliation(s)
- Shreosi Chatterjee
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela, 769 008, Odisha, India
| | - Surajit Das
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela, 769 008, Odisha, India.
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3
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Rajasenan S, Osmani AH, Osmani SA. Modulation of sensitivity to gaseous signaling by sterol-regulatory hypoxic transcription factors in Aspergillus nidulans biofilm cells. Fungal Genet Biol 2022; 163:103739. [PMID: 36089227 DOI: 10.1016/j.fgb.2022.103739] [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: 05/20/2022] [Revised: 08/15/2022] [Accepted: 09/05/2022] [Indexed: 01/06/2023]
Abstract
Fungal biofilm founder cells experience self-generated hypoxia leading to dramatic changes in their cell biology. For example, during Aspergillus nidulans biofilm formation microtubule (MT) disassembly is triggered causing dispersal of EB1 from MT tips. This process is dependent on SrbA, a sterol regulatory element-binding transcription factor required for adaptation to hypoxia. We show that SrbA, an ER resident protein prior to activation, is proteolytically activated during early stages of biofilm formation and that, like SrbA itself, its activating proteases are also required for normal biofilm MT disassembly. In addition to SrbA, the AtrR transcription factor is also found to be required to modulate cellular responses to gaseous signaling during biofilm development. Using co-cultures, we further show that cells lacking srbA or atrR are capable of responding to biofilm generated gaseous microenvironments but are actually more sensitive to this signal than wild type cells. SrbA is a regulator of ergosterol biosynthetic genes and we find that the levels of seven GFP-tagged Erg proteins differentially accumulate during biofilm formation with various dependencies on SrbA for their accumulation. This uncovers a complex pattern of regulation with biofilm accumulation of only some Erg proteins being dependent on SrbA with others accumulating to higher levels in its absence. Because different membrane sterols are known to influence cell permeability to gaseous molecules, including oxygen, we propose that differential regulation of ergosterol biosynthetic proteins by SrbA potentially calibrates the cell's responsiveness to gaseous signaling which in turn modifies the cell biology of developing biofilm cells.
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Affiliation(s)
- Shobhana Rajasenan
- Ohio State University, Department of Molecular Genetics, 105 Biological Sciences Building, 484 West 12th Avenue, Columbus, OH 43210, United States
| | - Aysha H Osmani
- Ohio State University, Department of Molecular Genetics, 105 Biological Sciences Building, 484 West 12th Avenue, Columbus, OH 43210, United States
| | - Stephen A Osmani
- Ohio State University, Department of Molecular Genetics, 105 Biological Sciences Building, 484 West 12th Avenue, Columbus, OH 43210, United States.
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Wei T, Zheng N, Zheng H, Chen Y, Hong P, Liu W, Liu M. Proteomic Perspective of Azole Resistance in Aspergillus fumigatus Biofilm Extracellular Matrix in Response to Itraconazole. Med Mycol 2022; 60:myac084. [PMID: 36243954 DOI: 10.1093/mmy/myac084] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Azole-resistant Aspergillus fumigatus makes a major challenge to the chemotherapy for invasive aspergillosis, whereas cyp51A gene mutation is the most dominant mechanism for azole resistance. Moreover, biofilm contributes to drug resistance for A. fumigatus, and extracellular matrix (ECM) is essential to protect live cells from antifungal drugs. Therefore, we performed a comparative proteomic study on the biofilm ECM of both the wild-type and azole-resistant strains of A. fumigatus under azole pressure. In total, 2377 proteins were identified, of which 480 and 604 proteins with differential expression were obtained from the wild-type and azole-resistant A. fumigatus in exposure to itraconazole respectively (fold change > 2 or < 0.5, P-value < 0.05). We found that a high proportion of regulated proteins were located in cytoplasm, nucleus, and mitochondria. Meanwhile, GO and KEGG analyses revealed that metabolic process and ribosome pathway were significantly enriched. Particularly, differentially expressed proteins in response to azole pressure of both the wild-type and resistant strains were further analyzed. Our results indicated that these changes in biofilm ECM proteins were related to ergosterol synthesis, oxidative stress, efflux pumps, DNA repair, DNA replication, and transcription.
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Affiliation(s)
- Tianqi Wei
- Institute of Dermatology, Chinese Academy of Medical Science and Peking Union Medical College, Nanjing, China
| | - Nan Zheng
- Medical School, Nanjing University, Nanjing, China
| | - Hailin Zheng
- Institute of Dermatology, Chinese Academy of Medical Science and Peking Union Medical College, Nanjing, China
| | - Yuping Chen
- Institute of Dermatology, Chinese Academy of Medical Science and Peking Union Medical College, Nanjing, China
| | - Pianpian Hong
- Institute of Dermatology, Chinese Academy of Medical Science and Peking Union Medical College, Nanjing, China
| | - Weida Liu
- Institute of Dermatology, Chinese Academy of Medical Science and Peking Union Medical College, Nanjing, China
- Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China
- Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs, Nanjing, China
| | - Musang Liu
- Institute of Dermatology, Chinese Academy of Medical Science and Peking Union Medical College, Nanjing, China
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5
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Subroto E, van Neer J, Valdes I, de Cock H. Growth of Aspergillus fumigatus in Biofilms in Comparison to Candida albicans. J Fungi (Basel) 2022; 8:48. [PMID: 35049988 PMCID: PMC8779434 DOI: 10.3390/jof8010048] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 12/29/2021] [Accepted: 12/31/2021] [Indexed: 12/18/2022] Open
Abstract
Biofilm formation during infections with the opportunistic pathogen Aspergillus fumigatus can be very problematic in clinical settings, since it provides the fungal cells with a protective environment. Resistance against drug treatments, immune recognition as well as adaptation to the host environment allows fungal survival in the host. The exact molecular mechanisms behind most processes in the formation of biofilms are unclear. In general, the formation of biofilms can be categorized roughly in a few stages; adhesion, conidial germination and development of hyphae, biofilm maturation and cell dispersion. Fungi in biofilms can adapt to the in-host environment. These adaptations can occur on a level of phenotypic plasticity via gene regulation. However, also more substantial genetic changes of the genome can result in increased resistance and adaptation in the host, enhancing the survival chances of fungi in biofilms. Most research has focused on the development of biofilms. However, to tackle developing microbial resistance and adaptation in biofilms, more insight in mechanisms behind genetic adaptations is required to predict which defense mechanisms can be expected. This can be helpful in the development of novel and more targeted antifungal treatments to combat fungal infections.
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Affiliation(s)
| | | | | | - Hans de Cock
- Molecular Microbiology Laboratory, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands; (E.S.); (J.v.N.); (I.V.)
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6
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Roudbary M, Vahedi-Shahandashti R, Santos ALSD, Roudbar Mohammadi S, Aslani P, Lass-Flörl C, Rodrigues CF. Biofilm formation in clinically relevant filamentous fungi: a therapeutic challenge. Crit Rev Microbiol 2021; 48:197-221. [PMID: 34358430 DOI: 10.1080/1040841x.2021.1950121] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Biofilms are highly-organized microbial communities attached to a biotic or an abiotic surface, surrounded by an extracellular matrix secreted by the biofilm-forming cells. The majority of fungal pathogens contribute to biofilm formation within tissues or biomedical devices, leading to serious and persistent infections. The clinical significance of biofilms relies on the increased resistance to conventional antifungal therapies and suppression of the host immune system, which leads to invasive and recurrent fungal infections. While different features of yeast biofilms are well-described in the literature, the structural and molecular basis of biofilm formation of clinically related filamentous fungi has not been fully addressed. This review aimed to address biofilm formation in clinically relevant filamentous fungi.
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Affiliation(s)
- Maryam Roudbary
- Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | | | - André Luis Souza Dos Santos
- Department of General Microbiology, Microbiology Institute Paulo de Góes, Federal University of Rio de Janeiro (UFRJ), Brazil
| | | | - Peyman Aslani
- Department of Parasitology and Mycology, Faculty of Medicine, Aja University of Medical Sciences, Tehran, Iran
| | - Cornelia Lass-Flörl
- Institute of Hygiene and Medical Microbiology, Medical University Innsbruck, Innsbruck, Austria
| | - Célia F Rodrigues
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
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7
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Gene Expression Analysis of Non-Clinical Strain of Aspergillus fumigatus (LMB-35Aa): Does Biofilm Affect Virulence? J Fungi (Basel) 2020; 6:jof6040376. [PMID: 33352977 PMCID: PMC7766361 DOI: 10.3390/jof6040376] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/12/2020] [Accepted: 12/16/2020] [Indexed: 12/18/2022] Open
Abstract
Aspergillus fumigatus LMB-35Aa, a saprophytic fungus, was used for cellulase production through biofilms cultures. Since biofilms usually favor virulence in clinical strains, the expression of the related genes of the LMB 35-Aa strain was analyzed by qPCR from the biomass of planktonic cultures and biofilms developed on polyester cloth and polystyrene microplates. For this, virulence-related genes reported for the clinical strain Af293 were searched in A. fumigatus LMB 35-Aa genome, and 15 genes were identified including those for the synthesis of cell wall components, hydrophobins, invasins, efflux transporters, mycotoxins and regulators. When compared with planktonic cultures at 37 °C, invasin gene calA was upregulated in both types of biofilm and efflux transporter genes mdr4 and atrF were predominantly upregulated in biofilms on polystyrene, while aspHs and ftmA were upregulated only in biofilms formed on polyester. Regarding the transcription regulators, laeA was downregulated in biofilms, and medA did not show a significant change. The effect of temperature was also evaluated by comparing the biofilms grown on polyester at 37 vs. 28 °C. Non-significant changes at the expression level were found for most genes evaluated, except for atrF, gliZ and medA, which were significantly downregulated at 37 °C. According to these results, virulence appears to depend on the interaction of several factors in addition to biofilms and growth temperature.
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8
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Sun W, Liu L, Yu Y, Yu B, Liang C, Ying H, Liu D, Chen Y. Biofilm-Related, Time-Series Transcriptome and Genome Sequencing in Xylanase-Producing Aspergillus niger SJ1. ACS OMEGA 2020; 5:19737-19746. [PMID: 32803069 PMCID: PMC7424707 DOI: 10.1021/acsomega.0c02501] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 07/20/2020] [Indexed: 05/15/2023]
Abstract
In this study, we found that biofilm formation is a critical factor affecting the activity of Aspergillus niger SJ1 xylanase. Xylanase activity increased 8.8% from 1046.88 to 1147.74 U/mL during A. niger SJ1 immobilized fermentation with biofilm formation. Therefore, we carried out the work of genomic analysis and biofilm-related time-series transcriptome analysis of A. niger SJ1 for better understanding of the ability of A. niger SJ to produce xylanase and biofilm formation. Genome annotation results revealed a complete biofilm polysaccharide component synthesis pathway in A. niger SJ1 and five proteins regarding xylanase synthesis. In addition, results of transcriptome analysis revealed that the genes involved in the synthesis of cell wall polysaccharides and amino acid anabolism were highly expressed in the biofilm. Furthermore, the expression levels of major genes in the gluconeogenesis pathway and mitogen-activated protein kinase pathway were examined.
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Affiliation(s)
- Wenjun Sun
- National
Engineering Research Center for Biotechnology, College of Biotechnology
and Pharmaceutical Engineering, Nanjing
Tech University, Nanjing 210000, China
- State
Key Laboratory of Materials-Oriented Chemical Engineering, College
of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 210000, China
| | - Li Liu
- National
Engineering Research Center for Biotechnology, College of Biotechnology
and Pharmaceutical Engineering, Nanjing
Tech University, Nanjing 210000, China
- State
Key Laboratory of Materials-Oriented Chemical Engineering, College
of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 210000, China
| | - Ying Yu
- National
Engineering Research Center for Biotechnology, College of Biotechnology
and Pharmaceutical Engineering, Nanjing
Tech University, Nanjing 210000, China
- State
Key Laboratory of Materials-Oriented Chemical Engineering, College
of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 210000, China
| | - Bin Yu
- National
Engineering Research Center for Biotechnology, College of Biotechnology
and Pharmaceutical Engineering, Nanjing
Tech University, Nanjing 210000, China
- State
Key Laboratory of Materials-Oriented Chemical Engineering, College
of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 210000, China
| | - Caice Liang
- National
Engineering Research Center for Biotechnology, College of Biotechnology
and Pharmaceutical Engineering, Nanjing
Tech University, Nanjing 210000, China
- State
Key Laboratory of Materials-Oriented Chemical Engineering, College
of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 210000, China
| | - Hanjie Ying
- National
Engineering Research Center for Biotechnology, College of Biotechnology
and Pharmaceutical Engineering, Nanjing
Tech University, Nanjing 210000, China
- State
Key Laboratory of Materials-Oriented Chemical Engineering, College
of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 210000, China
- School
of Chemical Engineering and Energy, Zhengzhou
University, Zhengzhou 450001, China
| | - Dong Liu
- National
Engineering Research Center for Biotechnology, College of Biotechnology
and Pharmaceutical Engineering, Nanjing
Tech University, Nanjing 210000, China
- State
Key Laboratory of Materials-Oriented Chemical Engineering, College
of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 210000, China
- School
of Chemical Engineering and Energy, Zhengzhou
University, Zhengzhou 450001, China
| | - Yong Chen
- National
Engineering Research Center for Biotechnology, College of Biotechnology
and Pharmaceutical Engineering, Nanjing
Tech University, Nanjing 210000, China
- State
Key Laboratory of Materials-Oriented Chemical Engineering, College
of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 210000, China
- . Phone: +86 25 86990001. Fax: +86 25 58139389
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9
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Garg A, Sharma GS, Goyal AK, Ghosh G, Si SC, Rath G. Recent advances in topical carriers of anti-fungal agents. Heliyon 2020; 6:e04663. [PMID: 32904164 PMCID: PMC7452444 DOI: 10.1016/j.heliyon.2020.e04663] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 11/22/2019] [Accepted: 08/05/2020] [Indexed: 12/19/2022] Open
Abstract
Fungal skin infections are the most common global issue for skin health. Fungal infections are often treated by topical or systemic anti-fungal therapy. Topical fungal therapy is usually preferred because of their targeted therapy and fewer side effects. Advanced topical carriers because of their distinct structural and functional features, overcome biopharmaceutical challenges associated with conventional drug delivery systems like poor retention and low bioavailability. Literature evidence indicated topical nanocarriers loaded with anti-fungal agents display superior therapeutic response with minimum toxicity. Nanocarriers often used for topical anti-fungal medication includes Solid-Lipid nanoparticles, Microemulsions, Liposomes, Niosomes, Microsponge, Nanogel, Nanoemulsion, Micelles etc. This review summarizes recent advances in novel strategies employed in topical carriers to improve the therapeutic performance of anti-fungal drugs.
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Affiliation(s)
- Abhinava Garg
- Department of Pharmaceutics, I.S.F.College of Pharmacy, Moga, Punjab, India
| | - Ganti S. Sharma
- Department of Pharmaceutics, I.S.F.College of Pharmacy, Moga, Punjab, India
| | - Amit K. Goyal
- School of Chemical Sciences and. Pharmacy, Central University of Rajasthan, India
| | - Goutam Ghosh
- Siksha ‘O’ Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
| | - Sudam Chandra Si
- Siksha ‘O’ Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
| | - Goutam Rath
- Siksha ‘O’ Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
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11
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Bamford NC, Le Mauff F, Subramanian AS, Yip P, Millán C, Zhang Y, Zacharias C, Forman A, Nitz M, Codée JDC, Usón I, Sheppard DC, Howell PL. Ega3 from the fungal pathogen Aspergillus fumigatus is an endo-α-1,4-galactosaminidase that disrupts microbial biofilms. J Biol Chem 2019; 294:13833-13849. [PMID: 31416836 DOI: 10.1074/jbc.ra119.009910] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 08/01/2019] [Indexed: 11/06/2022] Open
Abstract
Aspergillus fumigatus is an opportunistic fungal pathogen that causes both chronic and acute invasive infections. Galactosaminogalactan (GAG) is an integral component of the A. fumigatus biofilm matrix and a key virulence factor. GAG is a heterogeneous linear α-1,4-linked exopolysaccharide of galactose and GalNAc that is partially deacetylated after secretion. A cluster of five co-expressed genes has been linked to GAG biosynthesis and modification. One gene in this cluster, ega3, is annotated as encoding a putative α-1,4-galactosaminidase belonging to glycoside hydrolase family 114 (GH114). Herein, we show that recombinant Ega3 is an active glycoside hydrolase that disrupts GAG-dependent A. fumigatus and Pel polysaccharide-dependent Pseudomonas aeruginosa biofilms at nanomolar concentrations. Using MS and functional assays, we demonstrate that Ega3 is an endo-acting α-1,4-galactosaminidase whose activity depends on the conserved acidic residues, Asp-189 and Glu-247. X-ray crystallographic structural analysis of the apo Ega3 and an Ega3-galactosamine complex, at 1.76 and 2.09 Å resolutions, revealed a modified (β/α)8-fold with a deep electronegative cleft, which upon ligand binding is capped to form a tunnel. Our structural analysis coupled with in silico docking studies also uncovered the molecular determinants for galactosamine specificity and substrate binding at the -2 to +1 binding subsites. The findings in this study increase the structural and mechanistic understanding of the GH114 family, which has >600 members encoded by plant and opportunistic human pathogens, as well as in industrially used bacteria and fungi.
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Affiliation(s)
- Natalie C Bamford
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada.,Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - François Le Mauff
- Department of Microbiology and Immunology, Faculty of Medicine, McGill University, Montreal, Quebec H3A 2B4, Canada.,Infectious Disease and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada.,McGill Interdisciplinary Initiative in Infection and Immunity, Montreal, Quebec H3A 1Y2, Canada
| | - Adithya S Subramanian
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada.,Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Patrick Yip
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
| | - Claudia Millán
- Structural Biology, Instituto de Biología Molecular de Barcelona, CSIC, Carrer Baldiri Reixac 15, 3 A17, Barcelona 08028, Spain
| | - Yongzhen Zhang
- Leiden Institute of Chemistry, Leiden University, 2300RA Leiden, The Netherlands
| | - Caitlin Zacharias
- Department of Microbiology and Immunology, Faculty of Medicine, McGill University, Montreal, Quebec H3A 2B4, Canada.,Infectious Disease and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada.,McGill Interdisciplinary Initiative in Infection and Immunity, Montreal, Quebec H3A 1Y2, Canada
| | - Adam Forman
- Department of Chemistry, Faculty of Arts and Sciences, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Mark Nitz
- Department of Chemistry, Faculty of Arts and Sciences, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Jeroen D C Codée
- Leiden Institute of Chemistry, Leiden University, 2300RA Leiden, The Netherlands
| | - Isabel Usón
- Structural Biology, Instituto de Biología Molecular de Barcelona, CSIC, Carrer Baldiri Reixac 15, 3 A17, Barcelona 08028, Spain.,ICREA, Institució Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys, 23, E-08003 Barcelona, Spain
| | - Donald C Sheppard
- Department of Microbiology and Immunology, Faculty of Medicine, McGill University, Montreal, Quebec H3A 2B4, Canada .,Infectious Disease and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada.,McGill Interdisciplinary Initiative in Infection and Immunity, Montreal, Quebec H3A 1Y2, Canada
| | - P Lynne Howell
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada .,Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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12
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Zarrin M, Ganj F. Study of Hemolysin Gene " aspHS" and Its Phenotype in Aspergillus Fumigatus. Open Access Maced J Med Sci 2019; 7:2399-2403. [PMID: 31666836 PMCID: PMC6814479 DOI: 10.3889/oamjms.2019.349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 05/06/2019] [Accepted: 05/07/2019] [Indexed: 12/30/2022] Open
Abstract
AIM: The main goal of this study was to analysis the “aspHS” gene and its phenotype in A. fumigatus. METHODS: Fifty-three A. fumigatus strains, including environmental, clinical and reference isolates, were used in this research. PCR was carried out based on Asp-hemolysin gene sequence. Two restriction enzymes TagI and NcoI were employed for digestion of PCR products. RESULTS: PCR products of 180 and 450 bp were generated for all A. fumigatus isolates. Digestion of the aspHS gene 180 bp amplicons with TagI and 450 bp amplicons with TagI and NcoI produced the expected bands for most isolates. Hemolysin production of A. fumigatus isolates was evaluated on sheep blood agar (SBA). CONCLUSION: In conclusion, our results provide evidence hemolysin activity and analysis of aspHS gene of A. fumigatus. These data may be useful in early diagnosis of A. fumigatus infections.
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Affiliation(s)
- Majid Zarrin
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Department of Medical Mycology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Farzaneh Ganj
- Department of Medical Mycology, Medical School, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
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Shishodia SK, Tiwari S, Shankar J. Resistance mechanism and proteins in Aspergillus species against antifungal agents. Mycology 2019; 10:151-165. [PMID: 31448149 PMCID: PMC6691784 DOI: 10.1080/21501203.2019.1574927] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 01/22/2019] [Indexed: 02/02/2023] Open
Abstract
Aspergillus species contain pathogenic and opportunistic fungal pathogens which have the potential
to cause mycosis (invasive aspergillosis) in humans. The existing antifungal drugs have
limitation largely due to the development of drug-resistant isolates. To gain insight
into the mechanism of action and antifungal drug resistance in Aspergillus species including biofilm formation, we have reviewed protein
data of Aspergillus species during interaction with
antifungals drugs (polynes, azoles and echinocandin) and phytochemicals (artemisinin,
coumarin and quercetin). Our analyses provided a list of Aspergillus proteins (72 proteins) that were abundant during interaction
with different antifungal agents. On the other hand, there are 26 proteins, expression
level of which is affected by more than two antifungal agents, suggesting the more
general response to the stress induced by the antifungal agents. Our analysis showed
enzymes from cell wall remodelling, oxidative stress response and energy metabolism are
the responsible factors for providing resistance against antifungal drugs in Aspergillus species and could be explored further in clinical
isolates. Also, these findings have clinical importance since the effect of drug
targeting different proteins can be potentiated by combination therapy. We have also
discussed the opportunities ahead to study the functional role of proteins from
environmental and clinical isolates of Aspergillus during
its interaction with the antifungal drugs. Abbreviations IPA: invasive pulmonary aspergillosis; IA: invasive aspergillosis; AmB: Amphotericin B;
CAS: Caspofungin; VRC: Voriconazole; ITC: Itraconazole; POS: Posaconazole; ART:
Artemisinin; QRT: Quercetin; CMR: Coumarin; MIC: minimal inhibitory concentration
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Affiliation(s)
- Sonia Kumari Shishodia
- Genomic Laboratory, Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, India
| | - Shraddha Tiwari
- Genomic Laboratory, Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, India
| | - Jata Shankar
- Genomic Laboratory, Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, India
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14
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Nowrousian M. Genomics and transcriptomics to study fruiting body development: An update. FUNGAL BIOL REV 2018. [DOI: 10.1016/j.fbr.2018.02.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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15
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Zhao S, Gibbons JG. A population genomic characterization of copy number variation in the opportunistic fungal pathogen Aspergillus fumigatus. PLoS One 2018; 13:e0201611. [PMID: 30071059 PMCID: PMC6072042 DOI: 10.1371/journal.pone.0201611] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 07/18/2018] [Indexed: 12/19/2022] Open
Abstract
Aspergillus fumigatus is a potentially deadly opportunistic fungal pathogen. Molecular studies have shaped our understanding of the genes, proteins, and molecules that contribute to A. fumigatus pathogenicity, but few studies have characterized genome-wide patterns of genetic variation at the population level. Of A. fumigatus genomic studies to-date, most focus mainly on single nucleotide polymorphisms and large structural variants, while overlooking the contribution of copy number variation (CNV). CNV is a class of small structural variation defined as loci that vary in their number of copies between individuals due to duplication, gain, or deletion. CNV can influence phenotype, including fungal virulence. In the present study, we characterized the population genomic patterns of CNV in a diverse collection of 71 A. fumigatus isolates using publicly available sequencing data. We used genome-wide single nucleotide polymorphisms to infer the population structure of these isolates and identified three populations consisting of at least 8 isolates. We then computationally predicted genome-wide CNV profiles for each isolate and conducted analyses at the species-, population-, and individual levels. Our results suggest that CNV contributes to genetic variation in A. fumigatus, with ~10% of the genome being CN variable. Our analysis indicates that CNV is non-randomly distributed across the A. fumigatus genome, and is overrepresented in subtelomeric regions. Analysis of gene ontology categories in genes that overlapped CN variants revealed an enrichment of genes related to transposable element and secondary metabolism functions. We further identified 72 loci containing 33 genes that showed divergent copy number profiles between the three A. fumigatus populations. Many of these genes encode proteins that interact with the cell surface or are involved in pathogenicity. Our results suggest that CNV is an important source of genetic variation that could account for some of the phenotypic differences between A. fumigatus populations and isolates.
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Affiliation(s)
- Shu Zhao
- Biology Department, Clark University, Worcester, Massachusetts, United States of America
| | - John G. Gibbons
- Biology Department, Clark University, Worcester, Massachusetts, United States of America
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Manfiolli AO, Dos Reis TF, de Assis LJ, de Castro PA, Silva LP, Hori JI, Walker LA, Munro CA, Rajendran R, Ramage G, Goldman GH. Mitogen activated protein kinases (MAPK) and protein phosphatases are involved in Aspergillus fumigatus adhesion and biofilm formation. Cell Surf 2018; 1:43-56. [PMID: 32743127 PMCID: PMC7389341 DOI: 10.1016/j.tcsw.2018.03.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/08/2018] [Accepted: 03/14/2018] [Indexed: 12/28/2022] Open
Abstract
The main characteristic of biofilm formation is extracellular matrix (ECM) production. The cells within the biofilm are surrounded by ECM which provides structural integrity and protection. During an infection, this protection is mainly against cells of the immune system and antifungal drugs. A. fumigatus forms biofilms during static growth on a solid substratum and in chronic aspergillosis infections. It is important to understand how, and which, A. fumigatus signal transduction pathways are important for the adhesion and biofilm formation in a host during infection. Here we investigated the role of MAP kinases and protein phosphatases in biofilm formation. The loss of the MAP kinases MpkA, MpkC and SakA had an impact on the cell surface and the ECM during biofilm formation and reduced the adherence of A. fumigatus to polystyrene and fibronectin-coated plates. The phosphatase null mutants ΔsitA and ΔptcB, involved in regulation of MpkA and SakA phosphorylation, influenced cell wall carbohydrate exposure. Moreover, we characterized the A. fumigatus protein phosphatase PphA. The ΔpphA strain was more sensitive to cell wall-damaging agents, had increased β-(1,3)-glucan and reduced chitin, decreased conidia phagocytosis by Dictyostelium discoideum and reduced adhesion and biofilm formation. Finally, ΔpphA strain was avirulent in a murine model of invasive pulmonary aspergillosis and increased the released of tumor necrosis factor alpha (TNF-α) from bone marrow derived macrophages (BMDMs). These results show that MAP kinases and phosphatases play an important role in signaling pathways that regulate the composition of the cell wall, extracellular matrix production as well as adhesion and biofilm formation in A. fumigatus.
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Affiliation(s)
- Adriana Oliveira Manfiolli
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Thaila Fernanda Dos Reis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Leandro José de Assis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Lilian Pereira Silva
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Juliana I Hori
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Louise A Walker
- School of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Carol A Munro
- School of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Ranjith Rajendran
- Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, College of Medical, Veterinary and Life Sciences, The University of Glasgow, 378 Sauchiehall Street, Glasgow G2 3JZ, UK
| | - Gordon Ramage
- Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, College of Medical, Veterinary and Life Sciences, The University of Glasgow, 378 Sauchiehall Street, Glasgow G2 3JZ, UK
| | - Gustavo H Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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17
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Paul S, Ludeña Y, Villena GK, Yu F, Sherman DH, Gutiérrez-Correa M. High-quality draft genome sequence of a biofilm forming lignocellulolytic Aspergillus niger strain ATCC 10864. Stand Genomic Sci 2017; 12:37. [PMID: 28725336 PMCID: PMC5514509 DOI: 10.1186/s40793-017-0254-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 07/12/2017] [Indexed: 01/01/2023] Open
Abstract
Filamentous fungus Aspergillus niger has high industrial value due to their lignocellulolytic enzyme activities and ATCC 10864 is one of the few type strains of A. niger which has a unique biofilm forming capability. Here we report the first draft genome sequence of A. niger ATCC 10864 strain. The genome of A. niger ATCC 10864 is 36,172,237 bp long and comprise of 310 scaffolds with 49.5% average GC content. A total of 10,804 protein-coding genes were predicted among which 10,761 genes were with putative functions. A. niger ATCC 10864 genome coded for 709 putative carbohydrate active enzyme families distributed in six functional categories and among them glycoside hydrolases (GHs) represent the most number of families (279). Genes that include pepA, brlA, exgA, LaeA, rodA, GCN have also been identified in this study, which may play a role in biofilm formation. This high-quality draft genome sequence will facilitate our understanding of the mechanisms behind fungal biofilm formation and higher lignocellulolytic enzyme production.
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Affiliation(s)
- Sujay Paul
- Laboratorio de Micología y Biotecnología, Universidad Nacional Agraria La Molina, Av. La Molina s/n, 12 Lima, Peru
| | - Yvette Ludeña
- Laboratorio de Micología y Biotecnología, Universidad Nacional Agraria La Molina, Av. La Molina s/n, 12 Lima, Peru
| | - Gretty K Villena
- Laboratorio de Micología y Biotecnología, Universidad Nacional Agraria La Molina, Av. La Molina s/n, 12 Lima, Peru
| | - Fengan Yu
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216 USA
| | - David H Sherman
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216 USA
| | - Marcel Gutiérrez-Correa
- Laboratorio de Micología y Biotecnología, Universidad Nacional Agraria La Molina, Av. La Molina s/n, 12 Lima, Peru
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18
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Abstract
The polysaccharide-rich wall, which envelopes the fungal cell, is pivotal to the maintenance of cellular integrity and for the protection of the cell from external aggressors - such as environmental fluxes and during host infection. This review considers the commonalities in the composition of the wall across the fungal kingdom, addresses how little is known about the assembly of the polysaccharide matrix, and considers changes in the wall of plant-pathogenic fungi during on and in planta growth, following the elucidation of infection structures requiring cell wall alterations. It highlights what is known about the phytopathogenic fungal wall and what needs to be discovered.
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Affiliation(s)
- Ivey Geoghegan
- Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, UK; School of Life Sciences, University of Nottingham, Nottingham, NG7 2RD, UK.
| | - Gero Steinberg
- School of Biosciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Sarah Gurr
- Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, UK; School of Biosciences, University of Exeter, Exeter, EX4 4QD, UK.
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19
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Costa-Orlandi CB, Sardi JCO, Pitangui NS, de Oliveira HC, Scorzoni L, Galeane MC, Medina-Alarcón KP, Melo WCMA, Marcelino MY, Braz JD, Fusco-Almeida AM, Mendes-Giannini MJS. Fungal Biofilms and Polymicrobial Diseases. J Fungi (Basel) 2017; 3:jof3020022. [PMID: 29371540 PMCID: PMC5715925 DOI: 10.3390/jof3020022] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 04/19/2017] [Accepted: 05/04/2017] [Indexed: 12/29/2022] Open
Abstract
Biofilm formation is an important virulence factor for pathogenic fungi. Both yeasts and filamentous fungi can adhere to biotic and abiotic surfaces, developing into highly organized communities that are resistant to antimicrobials and environmental conditions. In recent years, new genera of fungi have been correlated with biofilm formation. However, Candida biofilms remain the most widely studied from the morphological and molecular perspectives. Biofilms formed by yeast and filamentous fungi present differences, and studies of polymicrobial communities have become increasingly important. A key feature of resistance is the extracellular matrix, which covers and protects biofilm cells from the surrounding environment. Furthermore, to achieve cell–cell communication, microorganisms secrete quorum-sensing molecules that control their biological activities and behaviors and play a role in fungal resistance and pathogenicity. Several in vitro techniques have been developed to study fungal biofilms, from colorimetric methods to omics approaches that aim to identify new therapeutic strategies by developing new compounds to combat these microbial communities as well as new diagnostic tools to identify these complex formations in vivo. In this review, recent advances related to pathogenic fungal biofilms are addressed.
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Affiliation(s)
- Caroline B Costa-Orlandi
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Janaina C O Sardi
- Department of Physiological Sciences, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba SP 13414-018, Brazil.
| | - Nayla S Pitangui
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Haroldo C de Oliveira
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Liliana Scorzoni
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Mariana C Galeane
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Kaila P Medina-Alarcón
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Wanessa C M A Melo
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Mônica Y Marcelino
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Jaqueline D Braz
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Ana Marisa Fusco-Almeida
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Maria José S Mendes-Giannini
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
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20
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Anjo SI, Figueiredo F, Fernandes R, Manadas B, Oliveira M. A proteomic and ultrastructural characterization of Aspergillus fumigatus' conidia adaptation at different culture ages. J Proteomics 2017; 161:47-56. [PMID: 28365406 DOI: 10.1016/j.jprot.2017.03.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 03/09/2017] [Accepted: 03/24/2017] [Indexed: 02/08/2023]
Abstract
The airborne fungus Aspergillus fumigatus is one of the most common agents of human fungal infections with a remarkable impact on public health. However, A. fumigatus conidia atmospheric resistance and longevity mechanisms are still unknown. Therefore, in this work, the processes underlying conidial adaptation were studied by a time course evaluation of the proteomics and ultrastructural changes of A. fumigatus' conidia at three time-points selected according to relevant changes previously established in conidial survival rates. The proteomics characterization revealed that conidia change from a highly active metabolic to a dormant state, culminating in cell autolysis as revealed by the increased levels of hydrolytic enzymes. Structural characterization corroborates the proteomics data, with noticeable changes observed in mitochondria, nucleus and plasma membrane ultrastructure, accompanied by the formation of autophagic vacuoles. These changes are consistent with both apoptotic and autophagic processes, and indicate that the changes in protein levels may anticipate those in cell morphology. SIGNIFICANCE The findings presented in this work not only clarify the processes underlying conidial adaptation to nutrient limiting conditions but can also be exploited for improving infection control strategies and in the development of new therapeutical drugs. Additionally, the present study was deposited in a public database and thus, it may also be a valuable dataset to be used by the scientific community as a tool to understand and identified other potential targets associated with conidia resistance.
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Affiliation(s)
- Sandra I Anjo
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; Faculty of Sciences and Technology, University of Coimbra, 3030-790 Coimbra, Portugal; CNC.IBILI, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Francisco Figueiredo
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; IBMC - Institute for Molecular and Cell Biology, University of Porto, 4200-135 Porto, Portugal
| | - Rui Fernandes
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; IBMC - Institute for Molecular and Cell Biology, University of Porto, 4200-135 Porto, Portugal
| | - Bruno Manadas
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; CNC.IBILI, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Manuela Oliveira
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; Ipatimup - Institute of Molecular Pathology and Immunology of the University of Porto, 4200-135 Porto, Portugal; Biology Department, Faculty of Sciences, University of Porto, 4150-171 Porto, Portugal.
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21
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González-Ramírez AI, Ramírez-Granillo A, Medina-Canales MG, Rodríguez-Tovar AV, Martínez-Rivera MA. Analysis and description of the stages of Aspergillus fumigatus biofilm formation using scanning electron microscopy. BMC Microbiol 2016; 16:243. [PMID: 27756222 PMCID: PMC5069814 DOI: 10.1186/s12866-016-0859-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Accepted: 10/07/2016] [Indexed: 11/17/2022] Open
Abstract
Background Biofilms are a highly structured consortia of microorganisms that adhere to a substrate and are encased within an extracellular matrix (ECM) that is produced by the organisms themselves. Aspergillus fumigatus is a biotechnological fungus that has a medical and phytopathogenic significance, and its biofilm occurs in both natural and artificial environments; therefore, studies on the stages observed in biofilm formation are of great significance due to the limited knowledge that exists on this specific topic and because there are multiple applications that are being carried out. Results Growth curves were obtained from the soil and clinical isolates of the A. fumigatus biofilm formation. The optimal conditions for both of the isolates were inocula of 1 × 106 conidia/mL, incubated at 28 °C during 24 h; these showed stages similar to those described in classic microbial growth: the lag, exponential, and stationary phases. However, the biofilms formed at 37 °C were uneven. The A. fumigatus biofilm was similar regardless of the isolation source, but differences were presented according to the incubation temperature. The biofilm stages included the following: 1) adhesion to the plate surface (4 h), cell co-aggregation and exopolymeric substance (EPS) production; 2) conidial germination into hyphae (8-12 h), development, hyphal elongation, and expansion with channel formation (16-20 h); and 3) biofilm maturation as follows: mycelia development, hyphal layering networks, and channels formation, and high structural arrangement of the mycelia that included hyphal anastomosis and an extensive production of ECM (24 h); the ECM covered, surrounded and strengthened the mycelial arrangements, particular at 37 °C. In the clinical isolate, irregular fungal structures, such as microhyphae that are short and slender hyphae, occurred; 4) In cell dispersion, the soil isolate exhibited higher conidia than the clinical isolate, which had the capacity to germinate and generate new mycelia growth (24 h). In addition, we present images on the biofilm’s structural arrangement and chemical composition using fluorochromes to detect metabolic activity (FUNI) and mark molecules, such as chitin, DNA, mannose, glucose and proteins. Conclusions To our knowledge, this is the first time that, in vitro, scanning electronic microscopy (SEM) images of the stages of A. fumigatus biofilm formation have been presented with a particular emphasis on the high hyphal organization and in diverse ECM to observe biofilm maturation.
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Affiliation(s)
- Alejandra Itzel González-Ramírez
- Laboratorio de Micología Médica, Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas (ENCB), Instituto Politécnico Nacional (IPN), Carpio y Plan de Ayala s/n, Col. Casco de Santo Tomás, Del. Miguel Hidalgo, 11340, Mexico City, Mexico
| | - Adrián Ramírez-Granillo
- Unidad de Microscopía ENCB, Instituto Politécnico Nacional (IPN), 11340, Mexico City, Mexico
| | - María Gabriela Medina-Canales
- Laboratorio de Micología Médica, Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas (ENCB), Instituto Politécnico Nacional (IPN), Carpio y Plan de Ayala s/n, Col. Casco de Santo Tomás, Del. Miguel Hidalgo, 11340, Mexico City, Mexico
| | - Aída Verónica Rodríguez-Tovar
- Laboratorio de Micología Médica, Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas (ENCB), Instituto Politécnico Nacional (IPN), Carpio y Plan de Ayala s/n, Col. Casco de Santo Tomás, Del. Miguel Hidalgo, 11340, Mexico City, Mexico.
| | - María Angeles Martínez-Rivera
- Laboratorio de Micología Médica, Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas (ENCB), Instituto Politécnico Nacional (IPN), Carpio y Plan de Ayala s/n, Col. Casco de Santo Tomás, Del. Miguel Hidalgo, 11340, Mexico City, Mexico. .,Prolongación de Carpio y Plan de Ayala s/n, C.P. 11340, Ciudad de México, Mexico.
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22
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RNA Sequencing-Based Genome Reannotation of the Dermatophyte Arthroderma benhamiae and Characterization of Its Secretome and Whole Gene Expression Profile during Infection. mSystems 2016; 1:mSystems00036-16. [PMID: 27822542 PMCID: PMC5069957 DOI: 10.1128/msystems.00036-16] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 06/27/2016] [Indexed: 01/08/2023] Open
Abstract
Dermatophytoses (ringworm, jock itch, athlete’s foot, and nail infections) are the most common fungal infections, but their virulence mechanisms are poorly understood. Combining transcriptomic data obtained from growth under various culture conditions with data obtained during infection led to a significantly improved genome annotation. About 65% of the protein-encoding genes predicted with our protocol did not match the existing annotation for A. benhamiae. Comparing gene expression during infection on guinea pigs with keratin degradation in vitro, which is supposed to mimic the host environment, revealed the critical importance of using real in vivo conditions for investigating virulence mechanisms. The analysis of genes expressed in vivo, encoding cell surface and secreted proteins, particularly proteases, led to the identification of new allergen and virulence factor candidates. Dermatophytes are the most common agents of superficial mycoses in humans and animals. The aim of the present investigation was to systematically identify the extracellular, possibly secreted, proteins that are putative virulence factors and antigenic molecules of dermatophytes. A complete gene expression profile of Arthroderma benhamiae was obtained during infection of its natural host (guinea pig) using RNA sequencing (RNA-seq) technology. This profile was completed with those of the fungus cultivated in vitro in two media containing either keratin or soy meal protein as the sole source of nitrogen and in Sabouraud medium. More than 60% of transcripts deduced from RNA-seq data differ from those previously deposited for A. benhamiae. Using these RNA-seq data along with an automatic gene annotation procedure, followed by manual curation, we produced a new annotation of the A. benhamiae genome. This annotation comprised 7,405 coding sequences (CDSs), among which only 2,662 were identical to the currently available annotation, 383 were newly identified, and 15 secreted proteins were manually corrected. The expression profile of genes encoding proteins with a signal peptide in infected guinea pigs was found to be very different from that during in vitro growth when using keratin as the substrate. Especially, the sets of the 12 most highly expressed genes encoding proteases with a signal sequence had only the putative vacuolar aspartic protease gene PEP2 in common, during infection and in keratin medium. The most upregulated gene encoding a secreted protease during infection was that encoding subtilisin SUB6, which is a known major allergen in the related dermatophyte Trichophyton rubrum. IMPORTANCE Dermatophytoses (ringworm, jock itch, athlete’s foot, and nail infections) are the most common fungal infections, but their virulence mechanisms are poorly understood. Combining transcriptomic data obtained from growth under various culture conditions with data obtained during infection led to a significantly improved genome annotation. About 65% of the protein-encoding genes predicted with our protocol did not match the existing annotation for A. benhamiae. Comparing gene expression during infection on guinea pigs with keratin degradation in vitro, which is supposed to mimic the host environment, revealed the critical importance of using real in vivo conditions for investigating virulence mechanisms. The analysis of genes expressed in vivo, encoding cell surface and secreted proteins, particularly proteases, led to the identification of new allergen and virulence factor candidates.
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23
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Moloney NM, Owens RA, Doyle S. Proteomic analysis of Aspergillus fumigatus – clinical implications. Expert Rev Proteomics 2016; 13:635-49. [DOI: 10.1080/14789450.2016.1203783] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
| | | | - Sean Doyle
- Department of Biology, Maynooth University, Maynooth, Ireland
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24
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Kaltdorf M, Srivastava M, Gupta SK, Liang C, Binder J, Dietl AM, Meir Z, Haas H, Osherov N, Krappmann S, Dandekar T. Systematic Identification of Anti-Fungal Drug Targets by a Metabolic Network Approach. Front Mol Biosci 2016; 3:22. [PMID: 27379244 PMCID: PMC4911368 DOI: 10.3389/fmolb.2016.00022] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 05/24/2016] [Indexed: 11/13/2022] Open
Abstract
New antimycotic drugs are challenging to find, as potential target proteins may have close human orthologs. We here focus on identifying metabolic targets that are critical for fungal growth and have minimal similarity to targets among human proteins. We compare and combine here: (I) direct metabolic network modeling using elementary mode analysis and flux estimates approximations using expression data, (II) targeting metabolic genes by transcriptome analysis of condition-specific highly expressed enzymes, and (III) analysis of enzyme structure, enzyme interconnectedness ("hubs"), and identification of pathogen-specific enzymes using orthology relations. We have identified 64 targets including metabolic enzymes involved in vitamin synthesis, lipid, and amino acid biosynthesis including 18 targets validated from the literature, two validated and five currently examined in own genetic experiments, and 38 further promising novel target proteins which are non-orthologous to human proteins, involved in metabolism and are highly ranked drug targets from these pipelines.
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Affiliation(s)
- Martin Kaltdorf
- Department of Bioinformatics, Biocenter, University of Würzburg Würzburg, Germany
| | - Mugdha Srivastava
- Department of Bioinformatics, Biocenter, University of Würzburg Würzburg, Germany
| | - Shishir K Gupta
- Department of Bioinformatics, Biocenter, University of Würzburg Würzburg, Germany
| | - Chunguang Liang
- Department of Bioinformatics, Biocenter, University of Würzburg Würzburg, Germany
| | - Jasmin Binder
- Microbiology Institute - Clinical Microbiology, Immunology and Hygiene, Friedrich-Alexander University Erlangen-Nürnberg, University Hospital of Erlangen Erlangen, Germany
| | - Anna-Maria Dietl
- Division of Molecular Biology/Biocenter, Medical University Innsbruck Innsbruck, Austria
| | - Zohar Meir
- Aspergillus and Antifungal Research Laboratory, Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University Tel-Aviv, Israel
| | - Hubertus Haas
- Division of Molecular Biology/Biocenter, Medical University Innsbruck Innsbruck, Austria
| | - Nir Osherov
- Aspergillus and Antifungal Research Laboratory, Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University Tel-Aviv, Israel
| | - Sven Krappmann
- Microbiology Institute - Clinical Microbiology, Immunology and Hygiene, Friedrich-Alexander University Erlangen-Nürnberg, University Hospital of Erlangen Erlangen, Germany
| | - Thomas Dandekar
- Department of Bioinformatics, Biocenter, University of Würzburg Würzburg, Germany
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Abstract
In vivo, Aspergillus fumigatus grows as a typical biofilm with hyphae covered by an extracellular matrix (ECM) composed of polysaccharides, galactomannan, and galactosaminogalactan. α1,3 glucans and melanin are also constitutive of the ECM in aspergilloma but not in invasive aspergillosis. In vitro, two biofilm models were established to mimic the in vivo situation. The first model (model 1) uses submerged liquid conditions and is characterized by slow growth, while the second model (model 2) uses agar medium and aerial conditions and is characterized by rapid growth. The composition of the ECM was studied only in the second model and has been shown to be composed of galactomannan, galactosaminogalactan (GAG), and α1,3 glucans, melanin, antigens, and hydrophobins. The presence of extracellular DNA was detected in model 1 biofilm but not in model 2. Transcriptomic analysis employing both biofilm models showed upregulation of genes coding for proteins involved in the biosynthesis of secondary metabolites, adhesion, and drug resistance. However, most data on A. fumigatus biofilms have been obtained in vitro and should be confirmed using in vivo animal models. There is a need for new therapeutic antibiofilm strategies that focus on the use of combination therapy, since biofilm formation poses an important clinical problem due to their resistance to antifungal agents. Furthermore, in vivo investigations of A. fumigatus biofilms that incorporate the associated microbiota are needed. Such studies will add another layer of complexity to our understanding of the role of A. fumigatus biofilm during lung invasion.
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Intra- and interspecific diversity of ultrastructural markers in Scedosporium. Fungal Biol 2016; 120:147-54. [DOI: 10.1016/j.funbio.2015.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 07/29/2015] [Accepted: 08/04/2015] [Indexed: 11/21/2022]
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General Overview on Nontuberculous Mycobacteria, Biofilms, and Human Infection. J Pathog 2015; 2015:809014. [PMID: 26618006 PMCID: PMC4649093 DOI: 10.1155/2015/809014] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 10/15/2015] [Indexed: 11/17/2022] Open
Abstract
Nontuberculous mycobacteria (NTM) are emergent pathogens whose importance in human health has been growing. After being regarded mainly as etiological agents of opportunist infections in HIV patients, they have also been recognized as etiological agents of several infections on immune-competent individuals and healthcare-associated infections. The environmental nature of NTM and their ability to assemble biofilms on different surfaces play a key role in their pathogenesis. Here, we review the clinical manifestations attributed to NTM giving particular importance to the role played by biofilm assembly.
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Mora-Montes HM, Dantas ADS, Trujillo-Esquivel E, de Souza Baptista AR, Lopes-Bezerra LM. Current progress in the biology of members of the Sporothrix schenckii complex following the genomic era. FEMS Yeast Res 2015; 15:fov065. [PMID: 26260509 DOI: 10.1093/femsyr/fov065] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/05/2015] [Indexed: 12/13/2022] Open
Abstract
Sporotrichosis has been attributed for more than a century to one single etiological agent, Sporothrix schencki. Only eight years ago, it was described that, in fact, the disease is caused by several pathogenic cryptic species. The present review will focus on recent advances to understand the biology and virulence of epidemiologically relevant pathogenic species of the S. schenckii complex. The main subjects covered are the new clinical and epidemiological aspects including diagnostic and therapeutic challenges, the development of molecular tools, the genome database and the perspectives for study of virulence of emerging Sporothrix species.
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Affiliation(s)
- Héctor M Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, CP 36050, Guanajuato, Gto., México
| | - Alessandra da Silva Dantas
- Laboratório de Micologia Celular e Proteômica, Universidade do Estado do Rio de Janeiro (UERJ), CEP 20550-013 Rio de Janeiro, RJ, Brazil
| | - Elías Trujillo-Esquivel
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, CP 36050, Guanajuato, Gto., México
| | - Andrea R de Souza Baptista
- Laboratório de Micologia Médica e Molecular, Universidade Federal Fluminense (UFF), CEP 24210-130 Niterói, RJ, Brazil
| | - Leila M Lopes-Bezerra
- Laboratório de Micologia Celular e Proteômica, Universidade do Estado do Rio de Janeiro (UERJ), CEP 20550-013 Rio de Janeiro, RJ, Brazil
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29
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Khemiri A, Jouenne T, Cosette P. Proteomics dedicated to biofilmology: What have we learned from a decade of research? Med Microbiol Immunol 2015; 205:1-19. [PMID: 26068406 DOI: 10.1007/s00430-015-0423-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 06/03/2015] [Indexed: 12/31/2022]
Abstract
Advances in proteomics techniques over the past decade, closely integrated with genomic and physicochemical approach, have played a great role in developing knowledge of the biofilm lifestyle of bacteria. Despite bacterial proteome versatility, many studies have demonstrated the ability of proteomics approaches to elucidating the biofilm phenotype. Though these investigations have been largely used for biofilm studies in the last decades, they represent, however, a very low percentage of proteomics works performed up to now. Such approaches have offered new targets for combating microbial biofilms by providing a comprehensive quantitative and qualitative overview of their protein cell content. Herein, we summarized the state of the art in knowledge about biofilm physiology after one decade of proteomic analysis. In a second part, we highlighted missing research tracks for the next decade, emphasizing the emergence of posttranslational modifications in proteomic studies stemming from recent advances in mass spectrometry-based proteomics.
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Affiliation(s)
- Arbia Khemiri
- CNRS, UMR 6270, Laboratory "Polymères, Biopolymères, Surfaces", 76820, Mont-Saint-Aignan, France.
- University of Normandy, UR, Mont-Saint-Aignan, France.
- PISSARO Proteomic Facility, IRIB, 76820, Mont-Saint-Aignan, France.
| | - Thierry Jouenne
- CNRS, UMR 6270, Laboratory "Polymères, Biopolymères, Surfaces", 76820, Mont-Saint-Aignan, France
- University of Normandy, UR, Mont-Saint-Aignan, France
- PISSARO Proteomic Facility, IRIB, 76820, Mont-Saint-Aignan, France
| | - Pascal Cosette
- CNRS, UMR 6270, Laboratory "Polymères, Biopolymères, Surfaces", 76820, Mont-Saint-Aignan, France
- University of Normandy, UR, Mont-Saint-Aignan, France
- PISSARO Proteomic Facility, IRIB, 76820, Mont-Saint-Aignan, France
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30
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Desai JV, Mitchell AP, Andes DR. Fungal biofilms, drug resistance, and recurrent infection. Cold Spring Harb Perspect Med 2014; 4:4/10/a019729. [PMID: 25274758 DOI: 10.1101/cshperspect.a019729] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
A biofilm is a surface-associated microbial community. Diverse fungi are capable of biofilm growth. The significance of this growth form for infection biology is that biofilm formation on implanted devices is a major cause of recurrent infection. Biofilms also have limited drug susceptibility, making device-associated infection extremely difficult to treat. Biofilm-like growth can occur during many kinds of infection, even when an implanted device is not present. Here we summarize the current understanding of fungal biofilm formation, its genetic control, and the basis for biofilm drug resistance.
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Affiliation(s)
- Jigar V Desai
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
| | - Aaron P Mitchell
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
| | - David R Andes
- Department of Medicine, University of Wisconsin, Madison, Wisconsin 53705
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31
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Martins I, Hartmann DO, Alves PC, Martins C, Garcia H, Leclercq CC, Ferreira R, He J, Renaut J, Becker JD, Silva Pereira C. Elucidating how the saprophytic fungus Aspergillus nidulans uses the plant polyester suberin as carbon source. BMC Genomics 2014; 15:613. [PMID: 25043916 PMCID: PMC4117967 DOI: 10.1186/1471-2164-15-613] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 07/16/2014] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Lipid polymers in plant cell walls, such as cutin and suberin, build recalcitrant hydrophobic protective barriers. Their degradation is of foremost importance for both plant pathogenic and saprophytic fungi. Regardless of numerous reports on fungal degradation of emulsified fatty acids or cutin, and on fungi-plant interactions, the pathways involved in the degradation and utilisation of suberin remain largely overlooked. As a structural component of the plant cell wall, suberin isolation, in general, uses harsh depolymerisation methods that destroy its macromolecular structure. We recently overcame this limitation isolating suberin macromolecules in a near-native state. RESULTS Suberin macromolecules were used here to analyse the pathways involved in suberin degradation and utilisation by Aspergillus nidulans. Whole-genome profiling data revealed the complex degrading enzymatic machinery used by this saprophytic fungus. Initial suberin modification involved ester hydrolysis and ω-hydroxy fatty acid oxidation that released long chain fatty acids. These fatty acids were processed through peroxisomal β-oxidation, leading to up-regulation of genes encoding the major enzymes of these pathways (e.g. faaB and aoxA). The obtained transcriptome data was further complemented by secretome, microscopic and spectroscopic analyses. CONCLUSIONS Data support that during fungal growth on suberin, cutinase 1 and some lipases (e.g. AN8046) acted as the major suberin degrading enzymes (regulated by FarA and possibly by some unknown regulatory elements). Suberin also induced the onset of sexual development and the boost of secondary metabolism.
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Affiliation(s)
- Isabel Martins
- />Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Diego O Hartmann
- />Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Paula C Alves
- />Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Celso Martins
- />Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
- />Instituto de Biologia Experimental e Tecnológica (iBET), Av. da República, 2781-901 Oeiras, Portugal
| | - Helga Garcia
- />Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Céline C Leclercq
- />Proteomics Platform, Centre de Recherche Public - Gabriel Lippmann, Belvaux, Luxembourg
| | - Rui Ferreira
- />Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Ji He
- />Cancer Genomics Research Laboratory, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, (previously, the Scientific Computing department, Samuel Roberts Noble Foundation, USA, 8717 Grovemont Circle, 20877 Gaithersburg, MD USA
| | - Jenny Renaut
- />Proteomics Platform, Centre de Recherche Public - Gabriel Lippmann, Belvaux, Luxembourg
| | - Jörg D Becker
- />Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, 2780-156 Oeiras, Portugal
| | - Cristina Silva Pereira
- />Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
- />Instituto de Biologia Experimental e Tecnológica (iBET), Av. da República, 2781-901 Oeiras, Portugal
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Costa-Orlandi CB, Sardi JCO, Santos CT, Fusco-Almeida AM, Mendes-Giannini MJS. In vitro characterization of Trichophyton rubrum and T. mentagrophytes biofilms. BIOFOULING 2014; 30:719-727. [PMID: 24856309 DOI: 10.1080/08927014.2014.919282] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Dermatophytes are fungi responsible for a disease known as dermatophytosis. Biofilms are sessile microbial communities surrounded by extracellular polymeric substances (EPS) with increased resistance to antimicrobial agents and host defenses. This paper describes, for the first time, the characteristics of Trichophyton rubrum and T. mentagrophytes biofilms. Biofilm formation was analyzed by light microscopy, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) as well as by staining with crystal violet and safranin. Metabolic activity was determined using the XTT reduction assay. Both species were able to form mature biofilms in 72 h. T. rubrum biofilm produced more biomass and EPS and was denser than T. mentagrophytes biofilm. The SEM results demonstrated a coordinated network of hyphae in all directions, embedded within EPS in some areas. Research and characterization of biofilms formed by dermatophytes may contribute to the search of new drugs for the treatment of these mycoses and might inform future revisions with respect to the dose and duration of treatment of currently available antifungals.
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Affiliation(s)
- C B Costa-Orlandi
- a Department of Clinical Analysis, Clinical Mycology Laboratory, School of Pharmaceutical Sciences , UNESP - Universidade Estadual Paulista , Araraquara , SP 14801-902 , Brazil
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Ramage G, Robertson SN, Williams C. Strength in numbers: antifungal strategies against fungal biofilms. Int J Antimicrob Agents 2014; 43:114-20. [DOI: 10.1016/j.ijantimicag.2013.10.023] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 10/28/2013] [Indexed: 10/26/2022]
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In vitro analyses of mild heat stress in combination with antifungal agents against Aspergillus fumigatus biofilm. Antimicrob Agents Chemother 2013; 58:1443-50. [PMID: 24342649 DOI: 10.1128/aac.01007-13] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Aspergillus fumigatus biofilms still present a challenge for effective treatment in clinical settings. While mild heat stress has been introduced as a treatment for infectious diseases, the effectiveness of mild heat stress on A. fumigatus biofilm formation and antifungal susceptibility is still unknown. In the present study, confocal laser scanning microscopy (CLSM) was used to image and quantify Aspergillus fumigatus biofilm formation under three different regimens of continuous mild heat stress: at 37, 39, and 41°C. Furthermore, fungal growth has been investigated under the above conditions in combination with antifungal drugs (amphotericin B [AMB], micafungin [MCF], and voriconazole [VOC]) at early and late stages. CLSM analysis showed that higher temperatures induce earlier germination and greater hyphal elongation but poorer polar growth and reduced biofilm thickness. In the early stage of biofilm formation, the combination of treatment at 39 or 41°C with MCF or VOC produced no visible difference in biomass formation from similar treatments at 37°C with the same drug. Interestingly, AMB treatment at 37°C inhibited early stage biofilm formation to a much greater extent than at 39 and 41°C. At the late stage of biofilm formation, the mild heat treatments at 39 and 41°C with AMB, MCF, and VOC inhibited biomass formation compared to that at 37°C. The present data show that mild heat stress has a negative regulatory effect on biofilm formation in vitro, and antifungal drug improvement with mild heat treatment at late-stage biofilm formation provides useful indications of possible effective strategies for clinical management of aspergillosis.
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Pierce CG, Srinivasan A, Uppuluri P, Ramasubramanian AK, López-Ribot JL. Antifungal therapy with an emphasis on biofilms. Curr Opin Pharmacol 2013; 13:726-30. [PMID: 24011516 DOI: 10.1016/j.coph.2013.08.008] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 07/22/2013] [Accepted: 08/13/2013] [Indexed: 12/01/2022]
Abstract
Fungal infections are on the rise as advances in modern medicine prolong the lives of severely ill patients. Fungi are eukaryotic organisms and there are a limited number of targets for antifungal drug development; as a result the antifungal arsenal is exceedingly limited. Azoles, polyenes and echinocandins constitute the mainstay of antifungal therapy for patients with life-threatening mycoses. One of the main factors complicating antifungal therapy is the formation of fungal biofilms, microbial communities displaying resistance to most antifungal agents. A better understanding of fungal biofilms provides for new opportunities for the development of urgently needed novel antifungal agents and strategies.
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Affiliation(s)
- Christopher G Pierce
- Department of Biology, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA; South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA
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36
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Shopova I, Bruns S, Thywissen A, Kniemeyer O, Brakhage AA, Hillmann F. Extrinsic extracellular DNA leads to biofilm formation and colocalizes with matrix polysaccharides in the human pathogenic fungus Aspergillus fumigatus. Front Microbiol 2013; 4:141. [PMID: 23760756 PMCID: PMC3674311 DOI: 10.3389/fmicb.2013.00141] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 05/17/2013] [Indexed: 11/30/2022] Open
Abstract
The environmentally acquired fungal pathogen Aspergillus fumigatus causes a variety of severe diseases. Furthermore, it is often found colonizing the respiratory tract of patients suffering from cystic fibrosis. Conidia of this filamentous fungus adhere to substrate surfaces and germinate to form biofilms comprised of dense hyphal networks embedded in an adhesive extracellular matrix (ECM), built predominantly of polysaccharides. These fungal microconsortia are likely to be of clinical relevance, as they have also been observed during growth in the host and they confer drastically reduced susceptibility to antifungals. Little is known about environmental factors or signals contributing to the formation and structural organization of this polysaccharide matrix. Extracellular DNA (eDNA) is an abundant molecule in the mucus-rich surfaces in the lungs of cystic fibrosis patients. Here, we studied its influence on the biofilm establishment and progression of A. fumigatus. Using an in vitro biofilm model eDNA was identified as an efficient biofilm inducer promoting conidial surface adhesion and polysaccharide ECM production. Confocal laser scanning microscopy revealed entirely different ECM architectures depending on the substrates used for biofilm induction. In the presence of serum, adhesive polysaccharides were mainly localized to the hyphal tips appearing as cohesive threads or “halo” areas agglutinating the hyphae. Exogenous DNA altered the structural organization of the biofilm specifically by colocalizing to a grid-like bottom layer of ECM. These results indicate that biofilm formation in A. fumigatus is shaped by certain substrates and in response to host environmental signals.
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Affiliation(s)
- Iordana Shopova
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute Jena, Germany ; Department of Microbiology and Molecular Biology, Institute of Microbiology, Friedrich Schiller University Jena, Germany
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