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Penman R, Kariuki R, Shaw ZL, Dekiwadia C, Christofferson AJ, Bryant G, Vongsvivut J, Bryant SJ, Elbourne A. Gold nanoparticle adsorption alters the cell stiffness and cell wall bio-chemical landscape of Candida albicans fungal cells. J Colloid Interface Sci 2024; 654:390-404. [PMID: 37852025 DOI: 10.1016/j.jcis.2023.10.017] [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: 07/31/2023] [Revised: 09/08/2023] [Accepted: 10/04/2023] [Indexed: 10/20/2023]
Abstract
HYPOTHESIS Nanomaterials have been extensively investigated for a wide range of biomedical applications, including as antimicrobial agents, drug delivery vehicles, and diagnostic devices. The commonality between these biomedical applications is the necessity for the nanoparticle to interact with or pass through the cellular wall and membrane. Cell-nanomaterial interactions/uptake can occur in various ways, including adhering to the cell wall, forming aggregates on the surface, becoming absorbed within the cell wall itself, or transversing into the cell cytoplasm. These interactions are common to mammalian cells, bacteria, and yeast cells. This variety of interactions can cause changes to the integrity of the cell wall and the cell overall, but the precise mechanisms underpinning such interactions remain poorly understood. Here, we investigate the interaction between commonly investigated gold nanoparticles (AuNPs) and the cell wall/membrane of a model fungal cell to explore the general effects of interaction and uptake. EXPERIMENTS The interactions between 100 nm citrate-capped AuNPs and the cell wall of Candida albicans fungal cells were studied using a range of advanced microscopy techniques, including atomic force microscopy, confocal laser scanning microscopy, scanning electron microscopy, transmission electron microscopy, and synchrotron-FTIR micro-spectroscopy. FINDINGS In most cases, particles adhered on the cell surface, although instances of particles being up-taken into the cell cytoplasm and localised within the cell wall and membrane were also observed. There was a measurable increase in the stiffness of the fungal cell after AuNPs were introduced. Analysis of the synchrotron-FTIR data showed significant changes in spectral features associated with phospholipids and proteins after exposure to AuNPs.
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Affiliation(s)
- Rowan Penman
- School of Science, STEM College, RMIT University, Melbourne, VIC 3001, Australia
| | - Rashad Kariuki
- School of Science, STEM College, RMIT University, Melbourne, VIC 3001, Australia
| | - Z L Shaw
- School of Engineering, STEM College, RMIT University, Melbourne, VIC 3001, Australia
| | - Chaitali Dekiwadia
- RMIT Microscopy and Microanalysis Facility (RMMF), RMIT University, Melbourne, Victoria 3001, Australia
| | | | - Gary Bryant
- School of Science, STEM College, RMIT University, Melbourne, VIC 3001, Australia
| | - Jitraporn Vongsvivut
- Infrared Microspectroscopy (IRM) Beamline, ANSTO - Australian Synchrotron, Clayton, VIC 3168, Australia
| | - Saffron J Bryant
- School of Science, STEM College, RMIT University, Melbourne, VIC 3001, Australia.
| | - Aaron Elbourne
- School of Science, STEM College, RMIT University, Melbourne, VIC 3001, Australia.
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Masoumi H, Ghaemi A, Ghanadzadeh Gilani H. Surveying the elimination of hazardous heavy metal from the multi-component systems using various sorbents: a review. JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2022; 20:1047-1087. [PMID: 36406597 PMCID: PMC9672201 DOI: 10.1007/s40201-022-00832-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 08/18/2022] [Indexed: 06/16/2023]
Abstract
In this review, several adsorbents were studied for the elimination of heavy metal ions from multi-component wastewaters. These utilized sorbents are mineral materials, microbes, waste materials, and polymers. It was attempted to probe the structure and chemistry characteristics such as surface morphology, main functional groups, participated elements, surface area, and the adsorbent charges by SEM, FTIR, EDX, and BET tests. The uptake efficiency for metal ions, reusability studies, isotherm models, and kinetic relations for recognizing the adsorbent potentials. Besides, the influential factors such as acidity, initial concentration, time, and heat degree were investigated for selecting the optimum operating conditions in each of the adsorbents. According to the results, polymers especially chitosan, have displayed a higher adsorption capacity relative to the other common adsorbents owing to the excellent surface area and more functional groups such as amine, hydroxyl, and carboxyl species. The high surface area generates the possible active sites for trapping the particles, and the more effective functional groups can complex more metal ions from the polluted water. Also, it was observed that the uptake capacity of each metal ion in the multi-component solutions was different because the ionic radii of each metal ion were different, which influence the competition of metal ions for filling the active sites. Finally, the reusability of the polymers was suitable, because they can use several cycles which proves the economic aspect of the polymers as the adsorbent.
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Affiliation(s)
- Hadiseh Masoumi
- School of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology, Tehran, 13114-16846 Iran
| | - Ahad Ghaemi
- School of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology, Tehran, 13114-16846 Iran
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Githua KK, Maitho TE, Nguta JM, Okumu MO. Studies on the ethnopharmacology, antimicrobial activity, and toxicity of Catha edulis (Vahl.) Endl., in Sprague Dawley rats. F1000Res 2022; 11:286. [PMID: 37767078 PMCID: PMC10521044 DOI: 10.12688/f1000research.109243.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/15/2022] [Indexed: 09/29/2023] Open
Abstract
Background: The Mbeere South community of Embu County consume leaves of Catha edulis for its stimulant and euphoretic actions. Other indigenous uses of the plant are undocumented. Information on the pharmacology and safety of this plant is also scanty. This study aimed to document the ethnopharmacology, antimicrobial properties, and toxicity of C. edulis leaves collected from the Mbeere South community in Kenya. Methods: Ethnopharmacological data was collected from 35 informants using semi-structured questionnaires. Leaf extracts of C. edulis were prepared using acetone, water, and methanol. The antimicrobial properties of these extracts were evaluated against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. The toxicity of the aqueous extract was determined using hematological, biochemical, and histopathological parameters in male and female Sprague Dawley rats at 250 mg/kg, 500 mg/kg, and 1000 mg/kg doses over 28 days. p<0.05 was considered significant. Results: All informants were male, most were married, >50 years old, with >10 years of experience. The sources, local names, preparation, storage conditions, indications, frequency of use, dosage, and side effects of C. edulis were documented. All extracts were ineffective against E. coli, P. aeruginosa, and C. albicans. They had limited efficacy against B. cereus and S. aureus. Significant differences were observed in the hematological and biochemical parameters of rats at the tested doses. Low, intermediate, and high doses of the aqueous extract of C. edulis produced local congestion of the cardiac and hepatic vessels. Localized interstitial connective tissue proliferation, multifocal kidney interstitial hemorrhage, and localized tubular epithelium necrosis were also observed in female rats. Conclusions: The ethnobotanical uses of C. edulis among the Mbeere South community were documented for the first time. Limited antimicrobial efficacy and toxicity at high doses limit the use of leaves of C. edulis.
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Affiliation(s)
- Kevin Kariuki Githua
- Health, County Government of Embu, Embu, Embu, +254, Kenya
- Public Health, Pharmacology and Toxicology, University of Nairobi, Nairobi, Nairobi, 254, Kenya
| | - Timothy Elias Maitho
- Public Health, Pharmacology and Toxicology, University of Nairobi, Nairobi, Nairobi, 254, Kenya
| | - Joseph Mwanzia Nguta
- Public Health, Pharmacology and Toxicology, University of Nairobi, Nairobi, Nairobi, 254, Kenya
| | - Mitchel Otieno Okumu
- Public Health, Pharmacology and Toxicology, University of Nairobi, Nairobi, Nairobi, 254, Kenya
- Pharmacy, Jaramogi Oginga Odinga Teaching and Referral Hospital, Kisumu, Kisumu, +254, Kenya
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Wikandari R, Hasniah N, Taherzadeh MJ. The role of filamentous fungi in advancing the development of a sustainable circular bioeconomy. BIORESOURCE TECHNOLOGY 2022; 345:126531. [PMID: 34896535 DOI: 10.1016/j.biortech.2021.126531] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/03/2021] [Accepted: 12/04/2021] [Indexed: 06/14/2023]
Abstract
Human activities generate enormous amounts of organic wastes and residues. Filamentous fungi (FF) are able to grow on a broad range of substrates and survive over a wide spectrum of growth conditions. These characteristics enable FF to be exploited in biorefineries for various waste streams. Valorization of food industry byproducts into biomass and various arrays of value-added products using FF creates promising pathways toward a sustainable circular economy. This approach might also contribute to reaching the sustainable development goals set by the United Nations, particularly for zero hunger as well as affordable and clean energy. This paper presents the application of filamentous fungi in food, feeds, fuels, biochemicals, and biopolymers. The nutritional values, health benefits, and safety of foods derived from byproducts of food industries are also addressed. The technoeconomical feasibilities, sustainability aspects and challenges and future perspectives for biorefineries using filamentous fungi are discussed.
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Affiliation(s)
- Rachma Wikandari
- Department of Food and Agricultural Product Technology, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia.
| | - Nurul Hasniah
- Department of Food Technology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
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Endo-β-1,3-glucanase (GH16 Family) from Trichoderma harzianum Participates in Cell Wall Biogenesis but Is Not Essential for Antagonism Against Plant Pathogens. Biomolecules 2019; 9:biom9120781. [PMID: 31779176 PMCID: PMC6995588 DOI: 10.3390/biom9120781] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 11/20/2019] [Accepted: 11/20/2019] [Indexed: 12/22/2022] Open
Abstract
Trichoderma species are known for their ability to produce lytic enzymes, such as exoglucanases, endoglucanases, chitinases, and proteases, which play important roles in cell wall degradation of phytopathogens. β-glucanases play crucial roles in the morphogenetic-morphological process during the development and differentiation processes in Trichoderma species, which have β-glucans as the primary components of their cell walls. Despite the importance of glucanases in the mycoparasitism of Trichoderma spp., only a few functional analysis studies have been conducted on glucanases. In the present study, we used a functional genomics approach to investigate the functional role of the gluc31 gene, which encodes an endo-β-1,3-glucanase belonging to the GH16 family in Trichoderma harzianum ALL42. We demonstrated that the absence of the gluc31 gene did not affect the in vivo mycoparasitism ability of mutant T. harzianum ALL42; however, gluc31 evidently influenced cell wall organization. Polymer measurements and fluorescence microscopy analyses indicated that the lack of the gluc31 gene induced a compensatory response by increasing the production of chitin and glucan polymers on the cell walls of the mutant hyphae. The mutant strain became more resistant to the fungicide benomyl compared to the parental strain. Furthermore, qRT-PCR analysis showed that the absence of gluc31 in T. harzianum resulted in the differential expression of other glycosyl hydrolases belonging to the GH16 family, because of functional redundancy among the glucanases.
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Hoshi T, Yamazaki K, Sato Y, Shida T, Aoyagi T. Production of hollow-type spherical bacterial cellulose as a controlled release device by newly designed floating cultivation. Heliyon 2018; 4:e00873. [PMID: 30456320 PMCID: PMC6236009 DOI: 10.1016/j.heliyon.2018.e00873] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 10/13/2018] [Accepted: 10/16/2018] [Indexed: 12/04/2022] Open
Abstract
We developed a novel cultivating system for hollow-type spherical bacterial cellulose (HSBC) gel production without any molds or template. It consisted of floating aqueous medium droplet containing Gluconacetobacter xylinus (G. xylinus) at the boundary of two non-mixed silicone oil layers. The fibrils of bacterial cellulose (BC) were produced at the interface of water and oil phases. Fibril layers effectively thickened layer-by-layer and eventually formed a shell structure. The size of the HSBC gel can be controlled by the volume of dropped cell suspension. For cell suspensions of 50 μL and 10 μL, HSBC gels of approximately 4.0 mm and 2.5 mm were obtained, respectively. The shell of the HSBC gel is the gelatinous membrane formed by well-organized fibril networks; they comprised type-I crystal structure of cellulose. Additionally, we studied release profile of the fluorescein isothiocyanate-dextran (FITC-Dex) and observed that it released rapidly from the HSBC gels compared to from the BC gels obtained by the static culture method. The release behavior from HSBC gel agreed satisfactorily with Higuchi model. Therefore, the shell of HSBC gel is surely a thin gelatinous membrane of BC, and would be useful as a drug release device.
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Affiliation(s)
- Toru Hoshi
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, 1-8-14, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308, Japan
| | - Kazuyoshi Yamazaki
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, 1-8-14, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308, Japan
| | - Yuki Sato
- Graduate School of Science and Technology, Nihon University, 1-8-14, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308, Japan
| | - Takaya Shida
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, 1-8-14, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308, Japan
| | - Takao Aoyagi
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, 1-8-14, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308, Japan
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Bai Z, Ma Q, Dai Y, Yuan H, Ye J, Yu W. Spatial Heterogeneity of SOM Concentrations Associated with White-rot Versus Brown-rot Wood Decay. Sci Rep 2017; 7:13758. [PMID: 29062128 PMCID: PMC5653805 DOI: 10.1038/s41598-017-14181-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/05/2017] [Indexed: 11/08/2022] Open
Abstract
White- and brown-rot fungal decay via distinct pathways imparts characteristic molecular imprints on decomposing wood. However, the effect that a specific wood-rotting type of fungus has on proximal soil organic matter (SOM) accumulation remains unexplored. We investigated the potential influence of white- and brown-rot fungi-decayed Abies nephrolepis logs on forest SOM stocks (i.e., soil total carbon (C) and nitrogen (N)) and the concentrations of amino sugars (microbial necromass) at different depths and horizontal distances from decaying woody debris. The brown-rot fungal wood decay resulted in higher concentrations of soil C and N and a greater increase in microbial necromass (i.e., 1.3- to 1.7-fold greater) than the white-rot fungal wood decay. The white-rot sets were accompanied by significant differences in the proportions of the bacterial residue index (muramic acid%) with soil depth; however, the brown-rot-associated soils showed complementary shifts, primarily in fungal necromass, across horizontal distances. Soil C and N concentrations were significantly correlated with fungal rather than bacterial necromass in the brown-rot systems. Our findings confirmed that the brown-rot fungi-dominated degradation of lignocellulosic residues resulted in a greater SOM buildup than the white-rot fungi-dominated degradation.
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Affiliation(s)
- Zhen Bai
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Qiang Ma
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.
| | - Yucheng Dai
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Haisheng Yuan
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Ji Ye
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Wantai Yu
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.
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8
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Abstract
The fungal cell wall confers cell morphology and protection against environmental insults. For fungal pathogens, the cell wall is a key immunological modulator and an ideal therapeutic target. Yeast cell walls possess an inner matrix of interlinked β-glucan and chitin that is thought to provide tensile strength and rigidity. Yeast cells remodel their walls over time in response to environmental change, a process controlled by evolutionarily conserved stress (Hog1) and cell integrity (Mkc1, Cek1) signaling pathways. These mitogen-activated protein kinase (MAPK) pathways modulate cell wall gene expression, leading to the construction of a new, modified cell wall. We show that the cell wall is not rigid but elastic, displaying rapid structural realignments that impact survival following osmotic shock. Lactate-grown Candida albicans cells are more resistant to hyperosmotic shock than glucose-grown cells. We show that this elevated resistance is not dependent on Hog1 or Mkc1 signaling and that most cell death occurs within 10 min of osmotic shock. Sudden decreases in cell volume drive rapid increases in cell wall thickness. The elevated stress resistance of lactate-grown cells correlates with reduced cell wall elasticity, reflected in slower changes in cell volume following hyperosmotic shock. The cell wall elasticity of lactate-grown cells is increased by a triple mutation that inactivates the Crh family of cell wall cross-linking enzymes, leading to increased sensitivity to hyperosmotic shock. Overexpressing Crh family members in glucose-grown cells reduces cell wall elasticity, providing partial protection against hyperosmotic shock. These changes correlate with structural realignment of the cell wall and with the ability of cells to withstand osmotic shock. The C. albicans cell wall is the first line of defense against external insults, the site of immune recognition by the host, and an attractive target for antifungal therapy. Its tensile strength is conferred by a network of cell wall polysaccharides, which are remodeled in response to growth conditions and environmental stress. However, little is known about how cell wall elasticity is regulated and how it affects adaptation to stresses such as sudden changes in osmolarity. We show that elasticity is critical for survival under conditions of osmotic shock, before stress signaling pathways have time to induce gene expression and drive glycerol accumulation. Critical cell wall remodeling enzymes control cell wall flexibility, and its regulation is strongly dependent on host nutritional inputs. We also demonstrate an entirely new level of cell wall dynamism, where significant architectural changes and structural realignment occur within seconds of an osmotic shock.
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Gilmore SA, Naseem S, Konopka JB, Sil A. N-acetylglucosamine (GlcNAc) triggers a rapid, temperature-responsive morphogenetic program in thermally dimorphic fungi. PLoS Genet 2013; 9:e1003799. [PMID: 24068964 PMCID: PMC3778022 DOI: 10.1371/journal.pgen.1003799] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 07/30/2013] [Indexed: 01/24/2023] Open
Abstract
The monosaccharide N-acetylglucosamine (GlcNAc) is a major component of microbial cell walls and is ubiquitous in the environment. GlcNAc stimulates developmental pathways in the fungal pathogen Candida albicans, which is a commensal organism that colonizes the mammalian gut and causes disease in the setting of host immunodeficiency. Here we investigate GlcNAc signaling in thermally dimorphic human fungal pathogens, a group of fungi that are highly evolutionarily diverged from C. albicans and cause disease even in healthy individuals. These soil organisms grow as polarized, multicellular hyphal filaments that transition into a unicellular, pathogenic yeast form when inhaled by a human host. Temperature is the primary environmental cue that promotes reversible cellular differentiation into either yeast or filaments; however, a shift to a lower temperature in vitro induces filamentous growth in an inefficient and asynchronous manner. We found GlcNAc to be a potent and specific inducer of the yeast-to-filament transition in two thermally dimorphic fungi, Histoplasma capsulatum and Blastomyces dermatitidis. In addition to increasing the rate of filamentous growth, micromolar concentrations of GlcNAc induced a robust morphological transition of H. capsulatum after temperature shift that was independent of GlcNAc catabolism, indicating that fungal cells sense GlcNAc to promote filamentation. Whole-genome expression profiling to identify candidate genes involved in establishing the filamentous growth program uncovered two genes encoding GlcNAc transporters, NGT1 and NGT2, that were necessary for H. capsulatum cells to robustly filament in response to GlcNAc. Unexpectedly, NGT1 and NGT2 were important for efficient H. capsulatum yeast-to-filament conversion in standard glucose medium, suggesting that Ngt1 and Ngt2 monitor endogenous levels of GlcNAc to control multicellular filamentous growth in response to temperature. Overall, our work indicates that GlcNAc functions as a highly conserved cue of morphogenesis in fungi, which further enhances the significance of this ubiquitous sugar in cellular signaling in eukaryotes.
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Affiliation(s)
- Sarah A. Gilmore
- Department of Microbiology and Immunology and the Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, California, United States of America
| | - Shamoon Naseem
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
| | - James B. Konopka
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Anita Sil
- Department of Microbiology and Immunology and the Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, California, United States of America
- * E-mail:
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Novel cellulose-binding-domain protein in Phytophthora is cell wall localized. PLoS One 2011; 6:e23555. [PMID: 21887271 PMCID: PMC3160888 DOI: 10.1371/journal.pone.0023555] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 07/20/2011] [Indexed: 11/19/2022] Open
Abstract
Cellulose binding domains (CBD) in the carbohydrate binding module family 1 (CBM1) are structurally conserved regions generally linked to catalytic regions of cellulolytic enzymes. While widespread amongst saprophytic fungi that subsist on plant cell wall polysaccharides, they are absent amongst most plant pathogenic fungal cellulases. A genome wide survey for CBM1 was performed on the highly destructive plant pathogen Phytophthora infestans, a fungal-like Stramenopile, to determine if it harbored cellulolytic enzymes with CBM1. Only five genes were found to encode CBM1, and none were associated with catalytic domains. Surveys of other genomes indicated that the CBM1-containing proteins, lacking other domains, represent a unique group of proteins largely confined to the Stramenopiles. Immunolocalization of one of these proteins, CBD1, indicated that it is embedded in the hyphal cell wall. Proteins with CBM1 domains can have plant host elicitor activity, but tests with Agrobacterium-mediated in planta expression and synthetic peptide infiltration failed to identify plant hypersensitive elicitation with CBD1. A structural basis for differential elicitor activity is proposed.
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Selitrennikoff CP, Dalley NE, Sonneborn DR. Regulation of the hexosamine biosynthetic pathway in the water mold Blastocladiella emersonii: Sensitivity to endproduct inhibition is dependent upon the life cycle phase. Proc Natl Acad Sci U S A 2010; 77:5998-6002. [PMID: 16592895 PMCID: PMC350200 DOI: 10.1073/pnas.77.10.5998] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Chitin, a homopolymer of N-acetylglucosamine (GlcNAc), is the major macromolecular constituent of Blastocladiella emersonii cell walls. Zoospores do not possess a wall nor do they contain sufficient total hexosamine to account for the chitin content of the wall abruptly formed during germination. UDPGlcNAc, both the endproduct of hexosamine biosynthesis and the substrate for chitin synthesis, is present in zoospores in sufficient concentration to inhibit the first hexosamine pathway-specific enzyme activity. Net chitin accumulates in register with dry weight during exponential growth, but does not accumulate appreciably during the succeeding sporulation phase. Predicted relationships among net rates of chitin synthesis, UDPGlcNAc concentrations, and UDP plus UTP concentrations throughout the life cycle are explored, as are the assumptions upon which the predictions were based. We find that the sensitivity of the first hexosamine pathway-specific enzyme to endproduct inhibition is not constant throughout the life cycle; sensitivity is very high in the zoospore phase, decreases dramatically during germination, remains very low through the growth phase, and increases gradually to the zoospore level during sporulation. The organism appears to have evolved endproduct regulation in this case as an adaptation to "hard-times" phases of the life cycle-i.e., as a safeguard against overproduction of end product (UDPGlcNAc) when its utilization in cell wall (specifically chitin) synthesis is curtailed. Conversely, the organism effectively discards this mode of regulation during "good times," when the demands for end product are evidently greater than endproduct inhibition would otherwise permit.
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Affiliation(s)
- C P Selitrennikoff
- Department of Anatomy, University of Colorado Health Science Center, 4200 East Ninth Avenue, Denver, Colorado 80262
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12
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Strandberg GW, Shumate SE, Parrott JR. Microbial Cells as Biosorbents for Heavy Metals: Accumulation of Uranium by Saccharomyces cerevisiae and Pseudomonas aeruginosa. Appl Environ Microbiol 2010; 41:237-45. [PMID: 16345691 PMCID: PMC243671 DOI: 10.1128/aem.41.1.237-245.1981] [Citation(s) in RCA: 200] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Uranium accumulated extracellularly on the surfaces of Saccharomyces cerevisiae cells. The rate and extent of accumulation were subject to environmental parameters, such as pH, temperature, and interference by certain anions and cations. Uranium accumulation by Pseudomonas aeruginosa occurred intracellularly and was extremely rapid (<10 s), and no response to environmental parameters could be detected. Metabolism was not required for metal uptake by either organism. Cell-bound uranium reached a concentration of 10 to 15% of the dry cell weight, but only 32% of the S. cerevisiae cells and 44% of the P. aeruginosa cells within a given population possessed visible uranium deposits when examined by electron microscopy. Rates of uranium uptake by S. cerevisiae were increased by chemical pretreatment of the cells. Uranium could be removed chemically from S. cerevisiae cells, and the cells could then be reused as a biosorbent.
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Affiliation(s)
- G W Strandberg
- Chemical Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830
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Abstract
Biosorption of elements is a little understood phenomenon exhibited by some types of even nonliving microbial biomass. A common fungus Rhizopus arrhizus has been reported to take up uranium from aqueous solutions to the extent of 180 mg U(6+)/g. The mechanism of uranium sequestering by this type of biomass was studied by using experimental techniques such as electron microscopy, x-ray energy dispersion analysis, IR spectroscopy, and supporting evidence was obtained for a biosorption mechanism consisting of at least three processes. Uranium coordination and adsorption in the cell-wall chitin structure occur simultaneously and rapidly whereas precipitation of uranylhydroxide within the chitin microcrystalline cell-wall structure takes place at a lower rate. Interference of Fe(2+) and Zn(2+) coions with uranium biosorption is indicated.
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Affiliation(s)
- M Tsezos
- Department of Chemical Engineering, McGill University, Montreal, Quebec, Canada H3A 2A7
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Ahamed A, Vermette P. Effect of culture medium composition on Trichoderma reesei's morphology and cellulase production. BIORESOURCE TECHNOLOGY 2009; 100:5979-87. [PMID: 19592237 DOI: 10.1016/j.biortech.2009.02.070] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Revised: 02/03/2009] [Accepted: 02/03/2009] [Indexed: 05/05/2023]
Abstract
The objective of this study was to determine how fungal morphology influences the volumetric cellulase productivity of Trichoderma reesei cultured in four media with lactose and lactobionic acid as fed-batch in a 7 L stirred tank bioreactor. The use of a cellulose-yeast extract culture medium yielded the highest enzyme production with a volumetric enzyme activity of 69.8 U L(-1) h(-1), and a maximum fungal biomass of 14.7 g L(-1). These findings were associated with the following morphological characteristics of the fungus: total mycelia was 98% of total mean projected area, mean hyphae length of 10 mm, mean hyphae volume of 45.1 mm(3), mean hyphae diameter of 7.9 microm, number of branches 9, and number of tips per hypha 29. A positive correlation was found between the total mycelia, the number of tips and the volumetric enzyme productivity, indicating the weight of these variables on the enzyme productivity.
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Affiliation(s)
- Aftab Ahamed
- Laboratoire de Bioingénierie et de Biophysique de l'Université de Sherbrooke, Department of Chemical and Biotechnological Engineering, Université de Sherbrooke, 2500, Blvd de l'Université, Sherbrooke, Québec, Canada J1K 2R1
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15
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Dergunova MA, Alexeenko TV, Zhanaeva SY, Filyushina EE, Buzueva II, Kolesnikova OP, Kogan G, Korolenko TA. Characterization of the novel chemically modified fungal polysaccharides as the macrophage stimulators. Int Immunopharmacol 2009; 9:729-33. [DOI: 10.1016/j.intimp.2009.02.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Revised: 02/05/2009] [Accepted: 02/24/2009] [Indexed: 10/21/2022]
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16
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Grenville-Briggs LJ, Anderson VL, Fugelstad J, Avrova AO, Bouzenzana J, Williams A, Wawra S, Whisson SC, Birch PRJ, Bulone V, van West P. Cellulose synthesis in Phytophthora infestans is required for normal appressorium formation and successful infection of potato. THE PLANT CELL 2008; 20:720-38. [PMID: 18349153 PMCID: PMC2329931 DOI: 10.1105/tpc.107.052043] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2007] [Revised: 02/14/2008] [Accepted: 03/03/2008] [Indexed: 05/20/2023]
Abstract
Cellulose, the important structural compound of cell walls, provides strength and rigidity to cells of numerous organisms. Here, we functionally characterize four cellulose synthase genes (CesA) in the oomycete plant pathogen Phytophthora infestans, the causal agent of potato (Solanum tuberosum) late blight. Three members of this new protein family contain Pleckstrin homology domains and form a distinct phylogenetic group most closely related to the cellulose synthases of cyanobacteria. Expression of all four genes is coordinately upregulated during pre- and early infection stages of potato. Inhibition of cellulose synthesis by 2,6-dichlorobenzonitrile leads to a dramatic reduction in the number of normal germ tubes with appressoria, severe disruption of the cell wall in the preinfection structures, and a complete loss of pathogenicity. Silencing of the entire gene family in P. infestans with RNA interference leads to a similar disruption of the cell wall surrounding appressoria and an inability to form typical functional appressoria. In addition, the cellulose content of the cell walls of the silenced lines is >50% lower than in the walls of the nonsilenced lines. Our data demonstrate that the isolated genes are involved in cellulose biosynthesis and that cellulose synthesis is essential for infection by P. infestans.
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Affiliation(s)
- Laura J Grenville-Briggs
- Aberdeen Oomycete Group, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, AB25 2ZD, United Kingdom
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17
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18
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Torralba S, Raudaskoski M, Pedregosa AM, Laborda F. Effect of cytochalasin A on apical growth, actin cytoskeleton organization and enzyme secretion in Aspergillus nidulans. MICROBIOLOGY (READING, ENGLAND) 1998; 144 ( Pt 1):45-53. [PMID: 9537763 DOI: 10.1099/00221287-144-1-45] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The role of actin in apical growth and enzyme secretion in the filamentous fungus Aspergillus nidulans was studied by treating the hyphae with cytochalasin A (CA), which inhibits actin polymerization. Indirect immunofluorescence microscopy revealed actin at the tips of main hyphae and branches, and at the site of developing septa. CA inhibited the growth of the fungus and changed the growth pattern of hyphal tips from cylindrical tubes to spherical beads. The regions with swellings showed no actin fluorescence, and neither was actin seen in association with septa. After 4 h exposure, hyphae were able to resume the normal tip growth pattern in the presence of CA for a short period of time and new cylindrical hyphae, with actin fluorescence at the apex, emerged from the swollen tips. Later, the tips of the hyphae swelled again, which led to a beaded appearance. We also studied the effect of CA on the secretion of alpha- and beta-galactosidase. alpha-Galactosidase is secreted into the culture medium, whereas beta-galactosidase remains in the mycelium, with part of its activity bound to the cell wall. When A. nidulans mycelium was incubated in the presence of CA, a reduction in the secretion of alpha-galactosidase into the culture medium and a decrease in the alpha- and beta-galactosidase activities bound to the cell wall was detected. However, the CA dose used for the hyphae did not modify the secretion of the enzymes from protoplasts. Results described here provide evidence that a polymerized actin cytoskeleton is required for normal apical growth, hyphal tip shape and polarized enzyme secretion in A. nidulans. Cytochalasin-induced disruptions of the actin cytoskeleton could result in the alterations of apical growth and inhibition of enzyme secretion observed by blocking secretory vesicle transport to the apex.
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Affiliation(s)
- Sara Torralba
- Departament de Microbiología y Parasitología, Universidad de Alcalá de Henares, Carretera Madrid-Barcelona, Km 33, E-28871 Alcalá de Henares, Madrid, Spain
| | - Marjatta Raudaskoski
- Division of Plant Physiology, Department of Biosciences, University of Helsinki, PO Box 56, Viikinkaari 9, FIN-00014, University of Helsinki, Finland
| | - Ana María Pedregosa
- Departament de Microbiología y Parasitología, Universidad de Alcalá de Henares, Carretera Madrid-Barcelona, Km 33, E-28871 Alcalá de Henares, Madrid, Spain
| | - Fernando Laborda
- Departament de Microbiología y Parasitología, Universidad de Alcalá de Henares, Carretera Madrid-Barcelona, Km 33, E-28871 Alcalá de Henares, Madrid, Spain
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19
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Kennedy BK, Austriaco NR, Guarente L. Daughter cells of Saccharomyces cerevisiae from old mothers display a reduced life span. J Biophys Biochem Cytol 1994; 127:1985-93. [PMID: 7806576 PMCID: PMC2120297 DOI: 10.1083/jcb.127.6.1985] [Citation(s) in RCA: 240] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The yeast Saccharomyces cerevisiae typically divides asymmetrically to give a large mother cell and a smaller daughter cell. As mother cells become old, they enlarge and produce daughter cells that are larger than daughters derived from young mother cells. We found that occasional daughter cells were indistinguishable in size from their mothers, giving rise to a symmetric division. The frequency of symmetric divisions became greater as mother cells aged and reached a maximum occurrence of 30% in mothers undergoing their last cell division. Symmetric divisions occurred similarly in rad9 and ste12 mutants. Strikingly, daughters from old mothers, whether they arose from symmetric divisions or not, displayed reduced life spans relative to daughters from young mothers. Because daughters from old mothers were larger than daughters from young mothers, we investigated whether an increased size per se shortened life span and found that it did not. These findings are consistent with a model for aging that invokes a senescence substance which accumulates in old mother cells and is inherited by their daughters.
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Affiliation(s)
- B K Kennedy
- Department of Biology, Massachusetts Institute of Technology, Cambridge 02139
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20
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Abstract
A number of substances that directly or indirectly affect the cell walls of fungi have been identified. Those that actively interfere with the synthesis or degradation of polysaccharide components share the property of being produced by soil microbes as secondary metabolites. Compounds specifically interfering with chitin or beta-glucan synthesis have proven effective in studies of preclinical models of mycoses, though they appear to have a restricted spectrum of coverage. Semisynthetic derivatives of some of the natural products have offered improvements in activity, toxicology, or pharmacokinetic behavior. Compounds which act on the cell wall indirectly or by a secondary mechanism of action, such as the azoles, act against diverse fungi but are usually fungistatic in nature. Overall, these compounds are attractive candidates for further development.
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Affiliation(s)
- R F Hector
- Cutter Biological, Berkeley, California 94710
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21
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22
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Lipke PN, Kurjan J. Sexual agglutination in budding yeasts: structure, function, and regulation of adhesion glycoproteins. Microbiol Rev 1992; 56:180-94. [PMID: 1579109 PMCID: PMC372860 DOI: 10.1128/mr.56.1.180-194.1992] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The sexual agglutinins of the budding yeasts are cell adhesion proteins that promote aggregation of cells during mating. In each yeast species, complementary agglutinins are expressed by cells of opposite mating type that interact to mediate aggregation. Saccharomyces cerevisiae alpha-agglutinin and its analogs from other yeasts are single-subunit glycoproteins that contain N-linked and O-linked oligosaccharides. The N-glycosidase-sensitive carbohydrate is not necessary for activity. The proposed binding domain of alpha-agglutinin has features characteristic of the immunoglobulin fold structures of cell adhesion proteins of higher eukaryotes. The C-terminal region of alpha-agglutinin plays a role in anchoring the glycoprotein to the cell surface. The S. cerevisiae alpha-agglutinin and its analogs from other species contain multiple subunits; one or more binding subunits, which interact with the opposite agglutinin, are disulfide bonded to a core subunit, which mediates cell wall anchorage. The core subunits are composed of 80 to 95% O-linked carbohydrate. The binding subunits have less carbohydrate, and both carbohydrate and peptide play roles in binding. The alpha-agglutinin and alpha-agglutinin genes from S. cerevisiae have been cloned and shown to be regulated by the mating-type locus, MAT, and by pheromone induction. The agglutinins are necessary for mating under conditions that do not promote cell-cell contact. The role of the agglutinins therefore is to promote close interactions between cells of opposite mating type and possibly to facilitate the response to phermone, thus increasing the efficiency of mating. We speculate that they mediate enhanced response to sex pheromones by providing a synapse at the point of cell-cell contact, at which both pheromone secretion and cell fusion occur.
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Affiliation(s)
- P N Lipke
- Department of Biological Sciences, Hunter College, City University of New York, New York 10021
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23
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Gottlieb S, Altboum Z, Savage DC, Segal E. Adhesion of Candida albicans to epithelial cells effect of polyoxin D. Mycopathologia 1991; 115:197-205. [PMID: 1749403 DOI: 10.1007/bf00462227] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Data from our previous studies suggested that the fungal cell wall component, chitin, is involved in the adhesion of Candida albicans to mucosal surfaces. In the present study, we investigated the effect of polyoxin D, an inhibitor of chitin synthase, on the interaction of the fungus with epithelial cells. The effect of polyoxin D on Candida was evaluated in in vitro assays for its capacity to adhere to buccal epithelial cells (BEC), and by fluorescent-microscopy photometry and flow cytometry using cells stained with cellufluor (CF), a fluorochrome with affinity for chitin. C. albicans grown with and without polyoxin D was stained with CF and examined in a fluorescent microscope equipped with a photometer. Measurements of fluorescence revealed a wide range of intensity among C. albicans cells and a decreased intensity in polyoxin D treated cultures. Flow cytometry analyses of yeasts revealed 2 peaks of fluorescence intensity, and pointed to differences between polyoxin D treated and non-treated microorganisms. C. albicans stained with CF were separated into 2 subpopulations by flow cytometry according to fluorescence intensity. In vitro adhesion of each subpopulation to BEC was similar. Polyoxin D treated fungi showed significantly reduced adherence to BEC, as evaluated by a radioactivity assay with radiolabelled yeasts and by microscopic readings. The reduction in adhesion was Polyoxin D concentration dependent. These observations support our previous findings suggesting involvement of chitin in the attachment process of C. albicans (CBS562) to epithelial cells.
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Affiliation(s)
- S Gottlieb
- Department of Human Microbiology, Sackler School of Medicine, Tel-Aviv University, Israel
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24
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Hector RF, Zimmer BL, Pappagianis D. Evaluation of nikkomycins X and Z in murine models of coccidioidomycosis, histoplasmosis, and blastomycosis. Antimicrob Agents Chemother 1990; 34:587-93. [PMID: 2344165 PMCID: PMC171648 DOI: 10.1128/aac.34.4.587] [Citation(s) in RCA: 125] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Nikkomycins X and Z, competitive inhibitors of fungal chitin synthase, were evaluated as therapeutic agents in vitro and in mouse models of coccidioidomycosis, histoplasmosis, and blastomycosis. In vitro, the nikkomycins were found to be most effective against the highly chitinous, dimorphic fungi Coccidioides immitis and Blastomyces dermatitidis, were less effective against yeasts, and were virtually without effect on the filamentous fungus Aspergillus fumigatus. Additionally, by transmission electron microscopy, nikkomycin Z was highly disruptive to the cell wall and internal structure of the spherule-endospore phase of C. immitis in vitro. In vivo, nikkomycin Z was more effective than nikkomycin X, was also found to be superior on a milligram per milligram basis to the majority of azoles tested in the models of coccidioidomycosis and blastomycosis, and was moderately effective in histoplasmosis. A study of the pharmacokinetics in mice showed that nikkomycin Z was rapidly eliminated after intravenous infusion but that absorption after oral administration was sufficiently slow to allow inhibitory levels to persist for more than 2 h. Results of limited toxicology tests suggest that nikkomycin Z was well tolerated at the dosages employed.
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Affiliation(s)
- R F Hector
- Cutter Biological, Berkeley, California 94710
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25
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Benhamou N, Joosten MH, De Wit PJ. Subcellular Localization of Chitinase and of Its Potential Substrate in Tomato Root Tissues Infected by Fusarium oxysporum f. sp. radicis-lycopersici. PLANT PHYSIOLOGY 1990; 92:1108-20. [PMID: 16667378 PMCID: PMC1062423 DOI: 10.1104/pp.92.4.1108] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Antiserum raised against a tomato (Lycopersicon esculentum Mill.) chitinase (molecular mass of 26 kilodaltons) was used as a probe to study the subcellular localization of this enzyme in tomato root tissues infected with Fusarium oxysporum f. sp. radicis-lycopersici. A time-course experiment revealed that chitinase accumulated earlier in the incompatible interaction than in the compatible one. However, in both systems, chitinase deposition was largely correlated with pathogen distribution. The enzyme was found to accumulate in areas where host walls were in close contact with fungal cells. In contrast, the enzyme could not be detected in vacuoles and intracellular spaces. The substantial amount of chitinase found at the fungus cell surface supports the view of an antifungal activity. However, the preferential association of the enzyme with altered fungal wall areas indicates that chitinase activity is either preceded by the hydrolytic action of other enzymes such as beta-1,3-glucanases or coincides with these enzymes. The possibility that fungal glucans released through the action of beta-1,3-glucanases may act as elicitors of chitinase production is discussed.
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Affiliation(s)
- N Benhamou
- Département de phytologie, Faculté des sciences de l'agriculture et de l'alimentation, Université Laval, Sainte-Foy, Québec, Canada, G1K 7P4
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26
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Jabaji-Hare SH, Théiren J, Charest PM. High resolution cytochemical study of the vesicular-arbuscular mycorrhizal association, Glomus clarum×Allium porrum. THE NEW PHYTOLOGIST 1990; 114:481-496. [PMID: 33873978 DOI: 10.1111/j.1469-8137.1990.tb00416.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Roots of leek, colonized or not by Glomus clarum Nicolson & Schenck, were ultrastructurally examined for the presence of different sugars using lectin-gold complexes. N-acetyl-d-glucosamine (GlcNAc), N-acetyl-d-galactosamine (GalNAc), l-fucose (l-FUC), d-mannose (d-Man) and sialic acid sugar residues were localized in various cellular components of the mycorrhizal fungus. GlcNAc, GalNAc, d-Man and sialic acid residues were localized in the colonized host, particularly in the plasmalemma and cytoplasm surrounding the arbuscular hyphae. The same sugars were not present in the non-colonized host. These results indicated that the production of these sugars had been triggered during the plant-fungus association. In the interfacial matrix, GalNAc and d-Galactose (d-Gal) residues were present in moderate amounts. In cell walls and protoplasm of non-colonized and colonized hosts, mainly d-Gal was detected. Ribonucleic acid (RNA) was cytochemically localized in the fungus and host by means of a RNAse-gold complex. Of interest, was the specific localization of RNA in the granular wall layer of vesicles. The ultracytochemical results are discussed in relation to host-symbiont interaction, along with speculations on the function and significance of these macromolecules.
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Affiliation(s)
- S H Jabaji-Hare
- Departement de Phytologie, Faculté des Sciences de l'Agriculture et de l'Alimentation, Université Laval, Ste-Foy, Québec, Canada, G1K 7P4
| | - J Théiren
- Departement de Phytologie, Faculté des Sciences de l'Agriculture et de l'Alimentation, Université Laval, Ste-Foy, Québec, Canada, G1K 7P4
| | - P M Charest
- Departement de Phytologie, Faculté des Sciences de l'Agriculture et de l'Alimentation, Université Laval, Ste-Foy, Québec, Canada, G1K 7P4
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27
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Ponstein AS, Vos-Scheperkeuter GH, Jacobsen E, Feenstra WJ, Witholt B. Selective measurement of starch synthesizing enzymes in permeabilized potato tuber slices. PLANT PHYSIOLOGY 1990; 92:234-41. [PMID: 16667253 PMCID: PMC1062275 DOI: 10.1104/pp.92.1.234] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Osmotically permeabilized potato (Solanum tuberosum L.) tuber slices were used to study the biosynthesis of starch under semi in vivo conditions. Criteria to distinguish the various enzymes involved in starch biosynthesis were developed based on the characteristics of the enzymes in in vitro experiments. Branching enzyme activity was inhibited at pH 8.5 or higher, while the starch synthases functioned optimally between pH 8.8 and 9.1. Unprimed soluble starch synthase activity was only apparent in the presence of sodium citrate (0.4 molar or higher). Granulebound and primed soluble starch synthase were active in the absence of sodium citrate. Primed soluble starch synthase activity was susceptible to inhibition by 10 millimolar zinc sulfate, while granule-bound starch synthase activity was not. The incorporation of the Glc moiety of ADP-Glc into starch in tissue slices by the various starch synthases was consistent with in vitro data with respect to the affinity of the enzymes for substrate, the pH profile, the stimulation by citrate, and the inhibition by zinc sulfate. These data were used to determine the activity of each of the starch synthases in tissue slices: granule-bound and soluble starch synthase transferred 37 and 55 picomoles ADP-Glc per hour per milligram fresh weight into starch of permeabilized tissue slices at 30 degrees C and pH 9.1. In the presence of 0.5 molar sodium citrate, at least 40 picomoles ADP-Glc per hour per milligram fresh weight as transferred into starch by unprimed soluble starch synthase activity.
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Affiliation(s)
- A S Ponstein
- Groningen Biotechnology Center, Department of Biochemistry, Nijenborgh 16, 9747 AG Groningen, The Netherlands
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28
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Klebl F, Tanner W. Molecular cloning of a cell wall exo-beta-1,3-glucanase from Saccharomyces cerevisiae. J Bacteriol 1989; 171:6259-64. [PMID: 2509432 PMCID: PMC210497 DOI: 10.1128/jb.171.11.6259-6264.1989] [Citation(s) in RCA: 110] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A major protein of Saccharomyces cerevisiae cell walls is a 29-kilodalton glycoprotein which shows lectinlike binding to beta-1,3-glucan and chitin. It was solubilized by heating isolated cell walls at 90 degrees C and purified to homogeneity by running two high-pressure liquid chromatography columns. With the sequence information of the N terminus and seven peptides, two oligonucleotides were synthesized and the gene was cloned. Its sequence is similar to those of two plant beta-glucanases, and the protein was shown to possess beta-1,3-exoglucanase activity with laminarin as substrate. Haploid yeast cells contained one copy of the gene (BGL2). Gene disruption did not result in a phenotype.
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Affiliation(s)
- F Klebl
- Lehrstuhl für Zellbiologie und Pflanzenphysiologie, Universität Regensburg, Federal Republic of Germany
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29
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Broekaert WF, VAN Parijs J, Leyns F, Joos H, Peumans WJ. A Chitin-Binding Lectin from Stinging Nettle Rhizomes with Antifungal Properties. Science 1989; 245:1100-2. [PMID: 17838811 DOI: 10.1126/science.245.4922.1100] [Citation(s) in RCA: 225] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Rhizomes of stinging nettle contain a small-sized lectin that exhibits binding specificity toward chitin. This lectin inhibits growth of several phytopathogenic and saprophytic chitin-containing fungi in vitro. The antifungal action of the nettle lectin differs from the action of chitinases, which are a ubiquitous class of antifungal plant proteins. Moreover, the nettle lectin acts synergistically with chitinase in inhibiting fungal growth. The nettle lectin may be a promising candidate for possible applications in the genetic engineering of disease-resistant crops.
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30
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Joosten MH, De Wit PJ. Identification of Several Pathogenesis-Related Proteins in Tomato Leaves Inoculated with Cladosporium fulvum (syn. Fulvia fulva) as 1,3-beta-Glucanases and Chitinases. PLANT PHYSIOLOGY 1989; 89:945-51. [PMID: 16666646 PMCID: PMC1055948 DOI: 10.1104/pp.89.3.945] [Citation(s) in RCA: 95] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Inoculation of tomato (Lycopersicon esculentum) leaves with Cladosporium fulvum (Cooke) (syn. Fulvia fulva [Cooke] Cif) results in a marked accumulation of several pathogenesis-related (PR) proteins in the apoplast. Two predominant PR proteins were purified from apoplastic fluid by ion exchange chromatography followed by chromatofocusing. One protein (molecular mass [M(r)] 35 kilodaltons [kD], isoelectric point [pI] approximately 6.4) showed 1,3-beta-glucanase activity, while the other one (M(r)26 kD, pI approximately 6.1) showed chitinase activity. Identification of the products that were released upon incubation of the purified enzymes with laminarin or regenerated chitin revealed that both enzymes showed endo-activity. Using antisera raised against these purified enzymes from tomato and against chitinases and 1,3-beta-glucanases isolated from other plant species, one additional 1,3-beta-glucanase (M(r)33 kD) and three additional chitinases (M(r) 27, 30, and 32 kD) could be detected in apoplastic fluids or homogenates of tomato leaves inoculated with C. fulvum. Upon inoculation with C. fulvum, chitinase and 1,3-beta-glucanase activity in apoplastic fluids increased more rapidly in incompatible interactions than in compatible ones. The role of these hydrolytic enzymes, potentially capable of degrading hyphal walls of C. fulvum, is discussed in relation to active plant defense.
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Affiliation(s)
- M H Joosten
- Department of Phytopathology, Wageningen Agricultural University, P.O. Box 8025, 6700 EE Wageningen, The Netherlands
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31
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Sareneva H, Makarow M. Membrane biology in yeast as probed with enveloped viruses. Subcell Biochem 1989; 15:367-404. [PMID: 2508276 DOI: 10.1007/978-1-4899-1675-4_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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32
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Briza P, Ellinger A, Winkler G, Breitenbach M. Chemical composition of the yeast ascospore wall. The second outer layer consists of chitosan. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)37997-3] [Citation(s) in RCA: 111] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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33
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Abstract
Congo red may be applied as a fluorochrome to rapidly detect fungi in clinical specimens, tissue, and fungal culture preparations. This generally available stain is cost effective and simple to prepare. The stain may be prepared with potassium permanganate as a counterstain or with Formalin or glutaraldehyde as a fungicide.
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Affiliation(s)
- M Slifkin
- Department of Laboratory Medicine, Allegheny General Hospital, Pittsburgh, Pennsylvania 15212
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34
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Abstract
S. cerevisiae contains many mannose-rich glycoproteins that possess N- and O-linked carbohydrate chains, and both types may even occur on one and the same protein. The steps in the synthesis of asparagine-linked chains begin with assembly and transfer of the lipid-linked precursor to protein in a way common to all eucaryotes. Subsequent modifications lead to mannosyl extensions of various lengths, but complex type carbohydrate structures are not formed. Oligosaccharides O-linked to serine/threonine consist exclusively of mannose in S. cerevisiae. The mannose residue attached directly to the protein is transferred from Dol-P-Man in a unique way, which has been observed so far for fungal cells only. The cellular localization of the glycosylation reactions is summarized and the problem of transmembrane translocation of the sugar precursors at the ER and the Golgi is discussed. Some aspects of secretory (sec) and asparagine linked glycosylation (alg) mutants have been covered, and the various hypotheses related to the possible functions of this costly protein modification process are discussed. The article may also be helpful for those, who want to exploit the yeast's protein synthesizing machinery by genetically manipulating the cells.
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36
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Heidenreich F, Dierich MP. Candida albicans and Candida stellatoidea, in contrast to other Candida species, bind iC3b and C3d but not C3b. Infect Immun 1985; 50:598-600. [PMID: 2932390 PMCID: PMC262001 DOI: 10.1128/iai.50.2.598-600.1985] [Citation(s) in RCA: 120] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
It was demonstrated that complement-coated sheep erythrocytes bind to Candida albicans cells grown in serum-free RPMI 1640 medium. Testing of purified complement components proved that iC3b and C3d were responsible for the reaction, whereas C3b and C3b-H reacted only slightly if at all. Binding occurred only to C. albicans and C. stellatoidea, not to other species pathogenic to humans. There was evidence of a lectinlike nature of the effect.
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37
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Georgopapadakou NH, Smith SA. Chitin synthase in Candida albicans: comparison of digitonin-permeabilized cells and spheroplast membranes. J Bacteriol 1985; 162:826-9. [PMID: 3157678 PMCID: PMC218928 DOI: 10.1128/jb.162.2.826-829.1985] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The treatment of Candida albicans (yeast form) with digitonin or dimethyl sulfoxide permeabilized cells and caused the activation of chitin synthase in situ. Endogenous activation was completely prevented by the sulfhydryl reagents N-ethylmaleimide, p-chloromercuribenzoate, and 5,5'-dithiobis(2-nitrobenzoic acid); partially prevented by the protease inhibitors antipain, leupeptin, and N alpha-tosyl-L-lysyl chloromethyl ketone; and also partially prevented by EDTA. Thus, a clostripain-like protease may be involved in the endogenous activation phenomenon. The pH activity profile, cofactor requirements, and kinetic parameters of the endogenously activated chitin synthase were identical to those of the trypsin-activated enzyme in protoplast membranes.
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Bartnicki-Garcia S, Bracker CE, Lippman E, Ruiz-Herrera J. Chitosomes from the wall-less "slime" mutant of Neurospora crassa. Arch Microbiol 1984; 139:105-12. [PMID: 6240239 DOI: 10.1007/bf00401983] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Cell-free extracts from the wall-less slime mutant of Neurospora crassa and the mycelium of wild type exhibit similar chitin synthetase properties in specific activity, zymogenicity and a preferential intracellular localization of chitosomes. The yield of chitosomal chitin synthetase from slime cells was essentially the same irrespective of cell breakage procedure (osmotic lysis or ballistic disruption)--an indication that chitosomes are not fragments of larger membranes produced by harsh (ballistic) disruption procedures. The plasma membrane fraction, isolated from slime cells treated with concanavalin A, contained only a minute portion of the total chitin synthetase of the fungus. Most of the activity was in the cytoplasmic fraction; isopycnic sedimentation of this fraction on a sucrose gradient yielded a sharp band of chitosomes with a buoyant density = 1.125 g/cm3. Approximately 76% of the total chitin synthetase activity of the slime mutant was recovered in the chitosome band. Because of their low density, chitosomes could be cleanly separated from the rest of the membranous organelles of the fungus. Apparently, the lack of a cell wall in the slime mutant is not due to the absence of either chitosomes or zymogenic chitin synthetase.
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Gage RA, Van Wijngaarden W, Theuvenet AP, Borst-Pauwels GW, Haasnoot CA. Localization and identification of the compound causing peak ‘X’ in the 31P-NMR spectrum of Saccharomyces cerevisiae. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 1984. [DOI: 10.1016/0167-4889(84)90137-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Adams AE, Pringle JR. Relationship of actin and tubulin distribution to bud growth in wild-type and morphogenetic-mutant Saccharomyces cerevisiae. J Biophys Biochem Cytol 1984; 98:934-45. [PMID: 6365931 PMCID: PMC2113156 DOI: 10.1083/jcb.98.3.934] [Citation(s) in RCA: 718] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The distribution of actin in wild-type cells and in morphogenetic mutants of the budding yeast Saccharomyces cerevisiae was explored by staining cells with fluorochrome-labeled phallotoxins after fixing and permeabilizing the cells by several methods. The actin appeared to be localized in a set of cortical spots or patches, as well as in a network of cytoplasmic fibers. Bundles of filaments that may possibly correspond to the fibers visualized by fluorescence were observed with the electron microscope. The putative actin spots were concentrated in small and medium-sized buds and at what were apparently the sites of incipient bud formation on unbudded cells, whereas the putative actin fibers were generally oriented along the long axes of the mother-bud pairs. In several morphogenetic mutants that form multiple, abnormally elongated buds, the actin patches were conspicuously clustered at the tips of most buds, and actin fibers were clearly oriented along the long axes of the buds. There was a strong correlation between the occurrence of active growth at particular bud tips and clustering of actin spots at those same tips. Near the end of the cell cycle in wild-type cells, actin appeared to concentrate (as a cluster of spots or a band) in the neck region connecting the mother cell to its bud. Observations made using indirect immunofluorescence with a monoclonal anti-yeast-tubulin antibody on the morphogenetic mutant cdc4 (which forms multiple, abnormally elongated buds while the nuclear cycle is arrested) revealed the surprising occurrence of multiple bundles of cytoplasmic microtubules emanating from the one duplicated spindle-pole body per cell. It seems that most or all of the buds contain one or more of these bundles of microtubules, which often can be seen to extend to the very tips of the buds. These observations are consistent with the hypotheses that actin, tubulin, or both may be involved in the polarization of growth and localization of cell-wall deposition that occurs during the yeast cell cycle.
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Leal F, Ruiz-Herrera J, Villanueva JR, Larriba G. An examination of factors affecting the instability of Saccharomyces cerevisiae glucan synthetase in cell free extracts. Arch Microbiol 1984; 137:209-14. [PMID: 6232905 DOI: 10.1007/bf00414545] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Yeast beta(1--3) glucan synthetase is stimulated and stabilized by EDTA. Sucrose protects the enzyme from self-inactivation. Preincubation of cell free extracts at low sucrose concentrations indicates a slow transition of the enzyme towards dissociation. Transition kinetics at 30 degrees C and 0 degrees C in the presence and in the absence of sucrose are interpreted assuming that a subunit is thermolabile in the free state and that sucrose increases its stability. Magnesium is deleterous for glucan synthetase in cell-free extracts. Chaotropic agents inactivate glucan synthetase according to their capacity to solubilize and depolymerize biological compounds. Fluoride plays a special role in the activation of glucan synthetase. Its action appears to be dependent on the presence of GTP (or other nucleotides). The role of all these agents on the activity and stability of the enzyme is interpreted in a unified scheme.
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Pancaldi S, Poli F, Dall'Olio G, Vannini GL. Morphological anomalies induced by Congo red in Aspergillus niger. Arch Microbiol 1984; 137:185-7. [PMID: 6721628 DOI: 10.1007/bf00414540] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Aspergillus niger germ tubes were exposed for 6 h to 0.15 mg/ml of Congo red, a stain which prevents chitin microfibril assembly. The most evident alterations, detected under ultraviolet light and by transmission and scanning electron microscopy, concerned the hyphal tips which burst or, most frequently, expanded into bulges. In the latter structures, new hyphal tips appeared which, after giving rise to more or less developed hyphae, were themselves converted into new bulges. Therefore, segments derived from isotropic and polarized growth alternated in the organisms exposed to the dye. An interpretation of these abnormalities is advanced based upon the assumption that the maintainance of a regular gradient of wall viscosity in the hyphal extension zone depends primarily on the capability of glycan chains to form crystalline aggregates of increasing complexity.
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Pittet JL, Létoublon R, Frot-Coutaz J, Arpin N. Soluble uridine diphospho-D-glucose: mycosporin glucosyltransferase from spores of Ascochyta fabae Speg. PLANTA 1983; 159:159-164. [PMID: 24258137 DOI: 10.1007/bf00392987] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/1983] [Accepted: 04/26/1983] [Indexed: 06/02/2023]
Abstract
The enzyme properties of a soluble uridine 5'-diphosphate (UDP) glucose: mycosporin-2 glucosyltransferase from spores of Ascochyta fabae Speg. (Fungi imperfecti) were studied. The optimal conditions for the glucose transfer from UDP-glucose to the mycosporin-2 (the amide form being the best acceptor) were determined; for maximal activity the glucosyltransferase requires a pH of about 8.5 and the presence of divalent cations (Mn(2+) being more efficient than Ca(2+) or Mg(2+)). The reaction was not reversible in presence of large amounts of UDP.
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Affiliation(s)
- J L Pittet
- Départment de Biologie Végétale, Université C. Bernard, Lyon I, 43 Boulevard du 11 Novembre 1918, F-69622, Villeurbanne Cedex, France
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Milewski S, Chmara H, Borowski E. Growth inhibitory effect of antibiotic tetaine on yeast and mycelial forms of Candida albicans. Arch Microbiol 1983; 135:130-6. [PMID: 6357134 DOI: 10.1007/bf00408022] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The mycelial (M) form of Candida albicans is more sensitive to the action of the antibiotic tetaine than the yeast (Y) form. Tetaine, at low concentrations about 1 microgram/ml also inhibits Y-M transition. It causes severe deformation of cells, agglutination and inhibits septum formation in the yeast forms. Tetaine action is reversed by dipeptides in both forms and by tripeptides in M form. N-acetyl glucosamine is a powerful antagonist of tetaine action on both morphological forms. Tetaine action on mycelial forms is slightly antagonised by N-acetyl mannosamine and very powerfully by glutamine.
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Abstract
Stationary phase cultures of Candida albicans inoculated into fresh medium at 37 degrees C synchronously from buds at pH 4.5 and mycelia at pH 6.5. During bud formation, a filament ring forms just under the plasma membrane at the mother cell-bud junction at roughly the time of evagination. A filament ring also forms in mycelium-forming cells, but it appears later than in a budding cell and it is positioned along the elongating mycelium, on the average 2 microns from the mother cell-mycelium junction. Sections of filament rings in early and late budding cells and in mycelia appear similar. Each contains approximately 11 to 12 filaments equidistant from one another and closely associated with the plasma membrane. In both budding and mycelium-forming cells, the filament ring disappears when the primary septum grows inward. The close temporal and spatial association of the filament ring and the subsequent chitin-containing septum suggests a role for the filament ring in septum formation. In addition, a close temporal correlation is demonstrated between filament ring formation and the time at which cells become committed to bud formation at pH 4.5 and mycelium formation at pH 6.5. The temporal and spatial differences in filament ring formation between the two growth forms also suggest a simple model for the positioning of the filament ring.
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Jacobs CW, Szaniszlo PJ. Microtubule function and its relation to cellular development and the yeast cell cycle in Wangiella dermatitidis. Arch Microbiol 1982; 133:155-61. [PMID: 7165444 DOI: 10.1007/bf00413531] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The microtubule inhibitor nocodazole (methyl-5-[2-(thienylcarbonyl)-1H-benzimidazol-2-yl]-carbamate) prevented nuclear migration and nuclear division in yeasts and developing multicellular forms of the polymorphic fungus Wangiella dermatitidis. It did not prevent yeast bud formation during at least two or three budding cycles, and caused yeasts to accumulate as premitotic forms with one to three buds. The effects of the drug suggested that at least three control pathways were involved in the yeast cell cycle; that the nocodazole block point was separate from the execution points of two temperature-sensitive mutations which lead to multicellularity; and that microtubules were controlling neither the yeast budding process nor the development of multicellular forms.
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Pastor FI, Herrero E, Sentandreu R. Metabolism of Saccharomyces cerevisiae envelope mannoproteins. Arch Microbiol 1982; 132:144-8. [PMID: 6751259 DOI: 10.1007/bf00508720] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
By pulse and chase labeling experiments, two independent mannoprotein pools have been found associated with the Saccharomyces cerevisiae envelope. One of them probably corresponds to mannoproteins localized in the periplasmic space. These molecules showed a high turnover rate at 28 degrees C. The second pool is formed by intrinsic wall mannoproteins which are apparently stable for long periods of time, after a small initial turnover. These results suggest that at least part of the mannoproteins initially found in the periplasmic space may move into the wall. The time lag between the addition of the radioactive precursors and their incorporation in the cell envelope (20-30 min for amino acids and about 10 min for carbohydrate) indicates that protein formation and carbohydrate incorporation take place in succession. Moreover, bulk glycosylation of mannoproteins seems to occur close in time to the moment of secretion into the periplasmic space.
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Finkelman MA, Vardanis A. Pullulan Elaboration by
Aureobasidium pullulans
Protoplasts. Appl Environ Microbiol 1982; 44:121-7. [PMID: 16346047 PMCID: PMC241978 DOI: 10.1128/aem.44.1.121-127.1982] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Protoplasts of
Aureobasidium pullulans
are capable of producing pullulan. Biosynthesis of the polymer pullulan required induction with kinetics similar to those of whole cells. The protoplasts also produced a heteropolysaccharide component containing mannose, glucose, and galactose. The relative proportions of the pullulan and heteropolysaccharide fractions were a function of glucose concentration, with the pullulan content of the total polysaccharide rising from 20% at 2.5 mM glucose to 45% at 20 mM glucose. Elaboration of pullulan by both cells and protoplasts was sensitive to 0.6 M KCl, which was present as the osmotic stabilizer in protoplast experiments. The presence of KCl resulted in a shift in the pH optimum to a more acidic value. The molecular weight of the protoplast-derived pullulan was sharply reduced from the molecular weight of the whole-cell-derived product. Exposure of the protoplasts to proteolytic enzymes had no effect on polysaccharide elaboration.
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Affiliation(s)
- M A Finkelman
- Department of Microbiology and Immunology, The University of Western Ontario, and The London Research Centre, Agriculture Canada, London Ontario, Canada N6A 5B7
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Malowitz R, Pisano MA. Changes in cell wall carbohydrate composition of Paecilomyces persicinus P-10 M1 during growth and cephalosporin C production. Appl Environ Microbiol 1982; 43:916-23. [PMID: 7200757 PMCID: PMC241941 DOI: 10.1128/aem.43.4.916-923.1982] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The carbohydrate composition of the cell walls of Paecilomyces persicinus P-10 M1 was monitored daily for 6 days to detect any changes during growth and cephalosporin C production. Walls were isolated after mechanical breakage, sonication, and exposure to detergent. Major quantitative changes in cell wall carbohydrate composition accompanied a decrease in both cell weight and antibiotic production. Glucosamine content remained relatively constant in the 24- to 96-h cell walls and increased markedly in the 120- and 144-h preparations. The non-nitrogenous carbohydrate cell wall component, however, decreased significantly in the 48- and 120-h cell walls. Gas-liquid chromatographic analysis of the non-nitrogenous carbohydrate cell well fraction revealed the presence of glucose, the major component, mannose, galactose, and minute quantities of arabinose. Except for glucose, which was found to decrease moderately in the 120- and 144-h cell walls, the neutral sugars did not vary significantly with time.
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