Fungal HSP

Invertebrates are becoming more popular models for research on the immune system. The innate immunity possessed by insects shows both structural and functional similarity to the resistance displayed by mammals, and many processes occurring in insect hemocytes are similar to those that occur in mammals. The humoral immune response in insects acts by melanization, clotting and the production of reactive oxygen species and antimicrobial peptides, while the cellular immunity system is based on nodulation, encapsulation and phagocytosis...

The emergence and rapid spread of multidrug-resistance in human pathogenic microorganisms urgently require the development of novel therapeutic strategies for the treatment of infectious diseases. From this perspective, the antimicrobial properties of the natural plant-derived products may represent an important alternative therapeutic option to synthetic drugs. Among medicinal plants, the Cardiospermum halicacabum L. (C. halicacabum), belonging to Sapindaceae family, could be a very promising candidate for its antimicrobial activity against a wide range of microorganisms, including both Gram-positive and Gram-negative bacteria, as well as fungal pathogens...

The effect of hydrostatic pressure (HSP) and constant temperature fermentation (CTF) on the microbial community of soy sauce mash and metabolites (volatile and non-volatile) in raw soy sauce were investigated by multiphase methods. Soy sauce inoculated with yeasts (YG) or a mixture of yeasts and bacteria (MYG) were used in the present research. The results suggested that the effect of HSP resulted in decreasing of fungal community diversity, while CTF caused changes of the evenness of fungi species, which were also confirmed by alpha/beta diversity and clustering analysis...

The polyubiquitin gene is a highly conserved open reading frame that encodes different numbers of tandem ubiquitin repeats from different species, which play important roles in different biological processes. Metarhizium robertsii is a fungal entomopathogen that is widely applied in the biological control of pest insects. However, it is unclear whether the polyubiquitin gene is required for fungal development, stress tolerance, and virulence in the entomopathogenic fungus. In the present study, the polyubiquitin gene ( MrUBI4 , MAA_02160) was functionally characterized via gene deletion in M...

While sexual reproduction is pervasive in eukaryotic cells, the strategies employed by fungal species to achieve and complete sexual cycles is highly diverse and complex. Many fungi, including Saccharomyces cerevisiae and Schizosaccharomyces pombe, are homothallic (able to mate with their own mitotic descendants) because of homothallic switching (HO) endonuclease-mediated mating-type switching. Under laboratory conditions, the human fungal pathogen Candida albicans can undergo both heterothallic and homothallic (opposite- and same-sex) mating...

BACKGROUND: The fungal pathogen, Botrytis cinerea, infects a broad range of horticultural plants worldwide, resulting in significant economic losses. A derivative of chitosan, oligochitosan, has been reported to be an eco-friendly alternative to synthetic fungicides. RESULTS: Oligochitosan can greatly inhibit B. cinerea spore germination and induce protein carbonylation. To further investigate the molecular mechanism underlying the inhibitory effect, a comparative proteome analysis was conducted of oligochitosan-treated vs...

Heat-shock transcription factors (HSFs) with a HSF domain are regulators of fungal heat-shock protein (HSP) genes and many others vectoring heat-shock elements, to which the domain binds in response to heat shock and other stress cues. The fungal insect pathogen Beauveria bassiana harbors three HSF domain-containing orthologous to Hsf1, Sfl1, and Skn7 in many fungi. Here, we show that the three proteins are interrelated at transcription level, play overlapping or opposite roles in activating different families of 28 HSP genes and mediate differential expression of some genes required for asexual developmental and intracellular Na+ homeostasis...

The polyene antifungal amphotericin B (AmB) exerts a powerful and broad activity against a vast array of fungi and in general displays a remarkably low rate of antimicrobial resistance. Aspergillus terreus holds an exceptional position among the Aspergilli due to its intrinsic AmB resistance, in vivo and in vitro. Until now, the underlying mechanisms of polyene resistance were not well understood. This review will highlight the molecular basis of A. terreus and AmB resistance recently gained and will display novel data on the mode of action of AmB...

Heat shock proteins (HSPs) are immunogenic, ubiquitous class of molecular chaperones, which are induced in response to various environmental and microbial stressful conditions. It plays a vital role in maintaining cellular protein homeostasis in eukaryotic cells. In this study, we described a comprehensive comparative data by bioinformatics approach on three different full length cDNA sequences of HSP family at molecular level. The cDNA sequences of three HSPs were identified from constructed cDNA library of Channa striatus and named as CsCPN60, CsHSP60 and CsHSP70...

Although the utilisation of fungal biological control agents to kill insect pests is desirable, it is known that the outcome of infection may be influenced by a number of criteria, including whether or not the target insect is stressed. In the current work, topical treatment of larvae of the lepidopteran pest, Mamestra brassicae, with conidia of Beauveria bassiana, followed by a heat stress (HS; 37°C for 1h) 48h later, resulted in a similar level of larval survival to that occurring for no heat stress (No-HS), fungus-treated larvae...

The internal environment within animals or humans provides different conditions to invading saprophytic fungal pathogens, requiring the differential regulation of genes in comparison to environmental conditions. Understanding the mechanisms by which pathogens regulate genes within the host may be key in determining pathogen behavior within the host and may additionally facilitate further investigation into novel therapeutic agents. The heat shock protein (HSP)70 gene and its associated proteins have been frequently reported to be among the most highly expressed and dominant proteins present within various locations at physiological temperatures...

OBJECTIVES: Diagnosis of tuberculosis meningitis (TBM) remains challenging in tuberculosis (TB) endemic countries. The need for TB biomarkers arises, in part, from the difficulty of accurately diagnosing TBM with the available methods. PATIENTS AND METHODS: To explore the potential of host Hsps (Hsp 25, Hsp 60, Hsp 70 and Hsp 90) as an alternative marker in TBM diagnosis, we evaluated cerebrospinal fluid (CSF) sample of TBM (n=49), Pyogenic Meningitis (PM) (n=20), Viral Meningitis (VM) (n=09), Fungal Meningitis (FM) (n=04) and non infectious control (n=79) patients using indirect ELISA...

Treatment of fungal infections is difficult due to several reasons, such as side effects of drugs, emergence of resistant strains, and limited number of molecular targets for the drug compounds. In fungi, heat shock proteins (Hsps) have been implicated in several processes with the conserved molecular chaperone Hsp90 emerging as a potential target for antifungal therapy. It plays key cellular roles by eliciting molecular response to environmental changes, morphogenesis, antifungal resistance, and fungal pathogenicity...

Heat shock proteins (HSP) represent important antigenic targets for the immune response, playing an important role in the pathology and infectious diseases control. The purpose of this work was to investigate the levels of HSP60 and HSP70 specific antibodies in the bloodstream of patients with different bacterial infections and cancer, in order to evaluate their potential role as diagnosis markers of different infectious diseases. Detection of specific anti-HSP 60 and HSP 70 serum levels was performed by ELISA...

Temperature is a ubiquitous environmental variable which can profoundly influence the physiology of living cells as it changes over time and space. When yeast cells are exposed to a sublethal heat shock, normal metabolic functions become repressed and the heat shock transcription factor Hsf1 is activated, inducing heat shock proteins (HSPs). Candida albicans, the most prevalent human fungal pathogen, is an opportunistic pathogen that has evolved as a relatively harmless commensal of healthy individuals. Even though C...

The pathogenic yeast Cryptococcus neoformans secretes numerous proteins, such as heat shock proteins, by unconventional mechanisms during its interaction with host cells. Hsp70 is a conserved chaperone that plays important roles in various cellular processes, including the interaction of fungi with host immune cells. Here, we report that sera from individuals with cryptococcosis infection recognize a recombinant C. neoformans Hsp70 (Cn_rHsp70). Moreover, immunofluorescence assays using antibodies against Cn_rHsp70 revealed the localization of this protein at the cell surface mainly in association with the capsular network...

Changes in environmental conditions might be a stress factor for yeast cells. There are several mechanisms of stress tolerance, developed by the cell, which activate when the stress appears. Different transcription factors coordinate the expression of stress response genes. Msn2/4p regulate the expression of the general stress response. Heat shock defense involves heat shock proteins (Hsp), controlled by Hsf1p. Osmotic shock induces the MAP kinase cascade (HOG), whereas the oxidative stress response requires the YAP network...

Heat shock proteins (HSP) are produced in response to various stress stimuli to prevent cell damage. We evaluated the involvement of nitric oxide (NO) and reactive oxygen species (ROS) in the accumulation of Hsp70 proteins in tomato leaves induced by abiotic and biotic stress stimuli. A model system of leaf discs was used with two tomato genotypes, Solanum lycopersicum cv. Amateur and Solanum chmielewskii, differing in their resistance to fungal pathogen Oidium neolycopersici. Leaf discs were exposed to stress factors as heat shock and pathogen infection alone or in a combination, and treated with substances modulating endogenous NO and ROS levels...

The evolutionarily conserved Mediator complex is central to the regulation of gene transcription in eukaryotes because it serves as a physical and functional interface between upstream regulators and the Pol II transcriptional machinery. Nonetheless, its role appears to be context-dependent, and the detailed mechanism by which it governs the expression of most genes remains unknown. Here we investigate Mediator involvement in HSP (heat shock protein) gene regulation in the yeast Saccharomyces cerevisiae. We find that in response to thermal upshift, subunits representative of each of the four Mediator modules (Head, Middle, Tail, and Kinase) are rapidly, robustly, and selectively recruited to the promoter regions of HSP genes...

The present study reports molecular characterization of small heat shock protein gene in Indian isolates of Chaetomium globosum, C. perlucidum, C. reflexum, C. cochlioides and C. cupreum. Six isolates of C. globosum and other species showed a band of 630bp using specific primers. Amplified cDNA product of C. globosum (Cg 1) cloned and sequenced showed 603bp open reading frame encoding 200 amino-acids. The protein sequence had a molecular mass of 22 kDa and was therefore, named Hsp22. BlastX analysis revealed that the gene codes for a protein homologous to previously characterized Hsp22...