1
|
Kumari D, Sachivkina N, Pasrija R. Investigation of the influence of pH and temperature on melanization and survival under oxidative stress in Cryptococcus neoformans. Arch Microbiol 2024; 206:355. [PMID: 39017938 DOI: 10.1007/s00203-024-04080-7] [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: 04/16/2024] [Revised: 07/04/2024] [Accepted: 07/08/2024] [Indexed: 07/18/2024]
Abstract
Cryptococcus neoformans is an opportunistic pathogenic fungus that produces melanin during infection, an important virulence factor in Cryptococcal infections that enhances the ability of the fungus to resist immune defense. This fungus can synthesize melanin from a variety of substrates, including L-DOPA (L-3,4-dihydroxyphenylalanine). Since melanin protects the fungus from various stress factors such as oxidative, nitrosative, extreme heat and cold stress; we investigated the effects of environmental conditions on melanin production and survival. In this study, we investigated the effects of different pH values (5.6, 7.0 and 8.5) and temperatures (30 °C and 37 °C) on melanization and cell survival using a microtiter plate-based melanin production assay and an oxidative stress assay, respectively. In addition, the efficacy of compounds known to inhibit laccase involved in melanin synthesis, i.e., tunicamycin, β-mercaptoethanol, dithiothreitol, sodium azide and caspofungin on melanization was evaluated and their sensitivity to temperature and pH changes was measured. The results showed that melanin content correlated with pH and temperature changes and that pH 8.5 and 30 °C, were best for melanin production. Besides that, melanin production protects the fungal cells from oxidative stress induced by hydrogen peroxide. Thus, changes in pH and temperature drastically alter melanin production in C. neoformans and it correlates with the fungal survival. Due to the limited antifungal repertoire and the development of resistance in cryptococcal infections, the investigation of environmental conditions in the regulation of melanization and survival of C. neoformans could be useful for future research and clinical phasing.
Collapse
Affiliation(s)
- Deepika Kumari
- Department of Biochemistry, Maharshi Dayanand University, Rohtak, 124001, India
| | - Nadezhda Sachivkina
- Department of Microbiology, Peoples' Friendship University of Russia, Moscow, 117198, Russia
| | - Ritu Pasrija
- Department of Biochemistry, Maharshi Dayanand University, Rohtak, 124001, India.
| |
Collapse
|
2
|
Dakalbab S, Hamdy R, Holigová P, Abuzaid EJ, Abu-Qiyas A, Lashine Y, Mohammad MG, Soliman SSM. Uniqueness of Candida auris cell wall in morphogenesis, virulence, resistance, and immune evasion. Microbiol Res 2024; 286:127797. [PMID: 38851008 DOI: 10.1016/j.micres.2024.127797] [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: 04/19/2024] [Revised: 06/02/2024] [Accepted: 06/03/2024] [Indexed: 06/10/2024]
Abstract
Candida auris has drawn global attention due to its alarming multidrug resistance and the emergence of pan resistant strains. C. auris poses a significant risk in nosocomial candidemia especially among immunocompromised patients. C. auris showed unique virulence characteristics associated with cell wall including cell polymorphism, adaptation, endurance on inanimate surfaces, tolerance to external conditions, and immune evasion. Notably, it possesses a distinctive cell wall composition, with an outer mannan layer shielding the inner 1,3-β glucan from immune recognition, thereby enabling immune evasion and drug resistance. This review aimed to comprehend the association between unique characteristics of C. auris's cell wall and virulence, resistance mechanisms, and immune evasion. This is particularly relevant since the fungal cell wall has no human homology, providing a potential therapeutic target. Understanding the complex interactions between the cell wall and the host immune system is essential for devising effective treatment strategies, such as the use of repurposed medications, novel therapeutic agents, and immunotherapy like monoclonal antibodies. This therapeutic targeting strategy of C. auris holds promise for effective eradication of this resilient pathogen.
Collapse
Affiliation(s)
- Salam Dakalbab
- Research Institute for Medical and Health sciences, University of Sharjah, P.O. Box, Sharjah 27272, United Arab Emirates; College of Medicine, University of Sharjah, P.O. Box 27272, Sharjah, United Arab Emirates
| | - Rania Hamdy
- Research Institute for Science and Engineering (RISE), University of Sharjah, Sharjah 27272, United Arab Emirates; Faculty of Pharmacy, Zagazig University, P.O. Box 44519, Egypt
| | | | - Eman J Abuzaid
- Research Institute for Medical and Health sciences, University of Sharjah, P.O. Box, Sharjah 27272, United Arab Emirates
| | - Ameera Abu-Qiyas
- Research Institute for Medical and Health sciences, University of Sharjah, P.O. Box, Sharjah 27272, United Arab Emirates
| | - Yasmina Lashine
- Research Institute for Medical and Health sciences, University of Sharjah, P.O. Box, Sharjah 27272, United Arab Emirates; Faculty of Pharmacy, Zagazig University, P.O. Box 44519, Egypt
| | - Mohammad G Mohammad
- Research Institute for Medical and Health sciences, University of Sharjah, P.O. Box, Sharjah 27272, United Arab Emirates; Department of Medical Laboratory Sciences, College of Health Sciences, University of Sharjah, P.O. Box 27272, Sharjah, United Arab Emirates
| | - Sameh S M Soliman
- Research Institute for Medical and Health sciences, University of Sharjah, P.O. Box, Sharjah 27272, United Arab Emirates; Department of Medicinal Chemistry, College of Pharmacy, University of Sharjah, P.O. Box 27272, Sharjah, United Arab Emirates.
| |
Collapse
|
3
|
Silao FGS, Valeriano VD, Uddström E, Falconer E, Ljungdahl PO. Diverse mechanisms control amino acid-dependent environmental alkalization by Candida albicans. Mol Microbiol 2024; 121:696-716. [PMID: 38178569 DOI: 10.1111/mmi.15216] [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: 11/24/2023] [Revised: 12/12/2023] [Accepted: 12/14/2023] [Indexed: 01/06/2024]
Abstract
Candida albicans has the capacity to neutralize acidic growth environments by releasing ammonia derived from the catabolism of amino acids. The molecular components underlying alkalization and its physiological significance remain poorly understood. Here, we present an integrative model with the cytosolic NAD+-dependent glutamate dehydrogenase (Gdh2) as the principal ammonia-generating component. We show that alkalization is dependent on the SPS-sensor-regulated transcription factor STP2 and the proline-responsive activator Put3. These factors function in parallel to derepress GDH2 and the two proline catabolic enzymes PUT1 and PUT2. Consistently, a double mutant lacking STP2 and PUT3 exhibits a severe alkalization defect that nearly phenocopies that of a gdh2-/- strain. Alkalization is dependent on mitochondrial activity and in wild-type cells occurs as long as the conditions permit respiratory growth. Strikingly, Gdh2 levels decrease and cells transiently extrude glutamate as the environment becomes more alkaline. Together, these processes constitute a rudimentary regulatory system that counters and limits the negative effects associated with ammonia generation. These findings align with Gdh2 being dispensable for virulence, and based on a whole human blood virulence assay, the same is true for C. glabrata and C. auris. Using a transwell co-culture system, we observed that the growth and proliferation of Lactobacillus crispatus, a common component of the acidic vaginal microenvironment and a potent antagonist of C. albicans, is unaffected by fungal-induced alkalization. Consequently, although Candida spp. can alkalinize their growth environments, other fungal-associated processes are more critical in promoting dysbiosis and virulent fungal growth.
Collapse
Affiliation(s)
- Fitz Gerald S Silao
- Department of Molecular Biosciences, The Wenner-Gren Institute, Science for Life Laboratory (SciLifeLab), Stockholm University, Stockholm, Sweden
| | - Valerie Diane Valeriano
- Centre for Translational Microbiome Research (CTMR), Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Solna, Sweden
| | - Erika Uddström
- Department of Molecular Biosciences, The Wenner-Gren Institute, Science for Life Laboratory (SciLifeLab), Stockholm University, Stockholm, Sweden
| | - Emilie Falconer
- Department of Molecular Biosciences, The Wenner-Gren Institute, Science for Life Laboratory (SciLifeLab), Stockholm University, Stockholm, Sweden
| | - Per O Ljungdahl
- Department of Molecular Biosciences, The Wenner-Gren Institute, Science for Life Laboratory (SciLifeLab), Stockholm University, Stockholm, Sweden
| |
Collapse
|
4
|
Mahanta DK, Bhoi TK, Komal J, Samal I, Nikhil RM, Paschapur AU, Singh G, Kumar PVD, Desai HR, Ahmad MA, Singh PP, Majhi PK, Mukherjee U, Singh P, Saini V, Shahanaz, Srinivasa N, Yele Y. Insect-pathogen crosstalk and the cellular-molecular mechanisms of insect immunity: uncovering the underlying signaling pathways and immune regulatory function of non-coding RNAs. Front Immunol 2023; 14:1169152. [PMID: 37691928 PMCID: PMC10491481 DOI: 10.3389/fimmu.2023.1169152] [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: 02/18/2023] [Accepted: 08/07/2023] [Indexed: 09/12/2023] Open
Abstract
Multicellular organisms are constantly subjected to pathogens that might be harmful. Although insects lack an adaptive immune system, they possess highly effective anti-infective mechanisms. Bacterial phagocytosis and parasite encapsulation are some forms of cellular responses. Insects often defend themselves against infections through a humoral response. This phenomenon includes the secretion of antimicrobial peptides into the hemolymph. Specific receptors for detecting infection are required for the recognition of foreign pathogens such as the proteins that recognize glucans and peptidoglycans, together referred to as PGRPs and βGRPs. Activation of these receptors leads to the stimulation of signaling pathways which further activates the genes encoding for antimicrobial peptides. Some instances of such pathways are the JAK-STAT, Imd, and Toll. The host immune response that frequently accompanies infections has, however, been circumvented by diseases, which may have assisted insects evolve their own complicated immune systems. The role of ncRNAs in insect immunology has been discussed in several notable studies and reviews. This paper examines the most recent research on the immune regulatory function of ncRNAs during insect-pathogen crosstalk, including insect- and pathogen-encoded miRNAs and lncRNAs, and provides an overview of the important insect signaling pathways and effector mechanisms activated by diverse pathogen invaders.
Collapse
Affiliation(s)
- Deepak Kumar Mahanta
- Department of Entomology, Dr. Rajendra Prasad Central Agricultural University, Samastipur, Bihar, India
| | - Tanmaya Kumar Bhoi
- Forest Protection Division, Indian Council of Forestry Research and Education (ICFRE) - Arid Forest Research Institute (ICFRE-AFRI), Jodhpur, Rajasthan, India
| | - J. Komal
- Department of Entomology, Navsari Agricultural University, Navsari, Gujarat, India
| | - Ipsita Samal
- ICAR-National Research Centre on Litchi, Mushahari, Ramna, Muzaffarpur, Bihar, India
| | - R. M. Nikhil
- Division of Entomology, Indian Agricultural Research Institute, New Delhi, India
| | - Amit Umesh Paschapur
- Crop Protection Division, Indian Council of Agricultural Research (ICAR)-Vivekananda Parvatiya Krishi Anusandhan Sansthan, Almora, Uttarakhand, India
| | - Gaurav Singh
- The Directorate of Research, Maharana Pratap Horticultural University, Karnal, Haryana, India
| | - P. V. Dinesh Kumar
- Department of Plant Pathology University of Agricultural Sciences, Bengaluru, Karnataka, India
| | - H. R. Desai
- Department of Entomology, Main Cotton Research Station, Navsari Agricultural University, Gujarat, India
| | - Mohammad Abbas Ahmad
- Department of Entomology, Dr. Rajendra Prasad Central Agricultural University, Samastipur, Bihar, India
| | - P. P. Singh
- Department of Entomology, Tirhut College of Agriculture, Dr. Rajendra Prasad Central Agricultural University, Samastipur, Bihar, India
| | - Prasanta Kumar Majhi
- Department of Plant Breeding and Genetics, Odisha University of Agriculture and Technology, Bhubaneswar, Odisha, India
| | - U. Mukherjee
- Department of Entomology, Dr. Rajendra Prasad Central Agricultural University, Samastipur, Bihar, India
| | - Pushpa Singh
- Department of Entomology, Dr. Rajendra Prasad Central Agricultural University, Samastipur, Bihar, India
| | - Varun Saini
- Department of Entomology, Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, India
| | - Shahanaz
- Department of Entomology, College of Horticulture Mojerla, Sri Konda Laxman Telengana State Horticultural University, Wanaparthy, Telengana, India
| | - N. Srinivasa
- Department of Entomology and Agricultural Zoology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Yogesh Yele
- School of Crop Health Management Research, Council of Agricultural Research-National Institute of Biotic Stress Management (ICAR)- National Institute of Biotic Stress Management, Raipur, India
| |
Collapse
|
5
|
Cangui-Panchi SP, Ñacato-Toapanta AL, Enríquez-Martínez LJ, Salinas-Delgado GA, Reyes J, Garzon-Chavez D, Machado A. Battle royale: Immune response on biofilms – host-pathogen interactions. CURRENT RESEARCH IN IMMUNOLOGY 2023; 4:100057. [PMID: 37025390 PMCID: PMC10070391 DOI: 10.1016/j.crimmu.2023.100057] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 03/08/2023] [Accepted: 03/20/2023] [Indexed: 03/29/2023] Open
Abstract
The research interest of the scientific community in biofilm-forming microorganisms is growing due to the problems caused by their infections affecting humans and animals, mainly because of the difficulty of the host immune system in eradicating these microbial complex communities and the increasing antimicrobial resistance rates worldwide. This review describes the virulence factors and their interaction with the microbial communities of four well-known and highly biofilm-forming pathogens, more exactly, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus spp., and Candida spp. The innate and adaptive immune responses caused by the infection with these microorganisms and their evasion to the host immune system by biofilm formation are discussed in the present work. The relevance of the differences in the expression of certain virulence factors and the immune response in biofilm-associated infections when compared to planktonic infections is usually described as the biofilm architecture protects the pathogen and alters the host immune responses, here we extensively discussed these mechanisms.
Collapse
Affiliation(s)
- Sandra Pamela Cangui-Panchi
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Instituto de Microbiología, Laboratorio de Bacteriología, Quito, Ecuador
| | - Anahí Lizbeth Ñacato-Toapanta
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Instituto de Microbiología, Laboratorio de Bacteriología, Quito, Ecuador
| | - Leonardo Joshué Enríquez-Martínez
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Instituto de Microbiología, Laboratorio de Bacteriología, Quito, Ecuador
| | - Gabriela Alexandra Salinas-Delgado
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Instituto de Microbiología, Laboratorio de Bacteriología, Quito, Ecuador
| | - Jorge Reyes
- Hospital del Instituto Ecuatoriano de Seguridad Social (IESS) Quito-Sur, Quito, Ecuador
- Facultad de Ciencias Químicas, Universidad Central del Ecuador, Quito, Ecuador
| | - Daniel Garzon-Chavez
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias de la Salud, Quito, Ecuador
| | - António Machado
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Instituto de Microbiología, Laboratorio de Bacteriología, Quito, Ecuador
- Corresponding author.
| |
Collapse
|