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Zvolanek KM, Moore JE, Jarvis K, Moum SJ, Bright MG. Macrovascular blood flow and microvascular cerebrovascular reactivity are regionally coupled in adolescence. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.26.590312. [PMID: 38746187 PMCID: PMC11092525 DOI: 10.1101/2024.04.26.590312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Cerebrovascular imaging assessments are particularly challenging in adolescent cohorts, where not all modalities are appropriate, and rapid brain maturation alters hemodynamics at both macro- and microvascular scales. In a preliminary sample of healthy adolescents (n=12, 8-25 years), we investigated relationships between 4D flow MRI-derived blood velocity and blood flow in bilateral anterior, middle, and posterior cerebral arteries and BOLD cerebrovascular reactivity in associated vascular territories. As hypothesized, higher velocities in large arteries are associated with an earlier response to a vasodilatory stimulus (cerebrovascular reactivity delay) in the downstream territory. Higher blood flow through these arteries is associated with a larger BOLD response to a vasodilatory stimulus (cerebrovascular reactivity amplitude) in the associated territory. These trends are consistent in a case study of adult moyamoya disease. In our small adolescent cohort, macrovascular-microvascular relationships for velocity/delay and flow/CVR change with age, though underlying mechanisms are unclear. Our work emphasizes the need to better characterize this key stage of human brain development, when cerebrovascular hemodynamics are changing, and standard imaging methods offer limited insight into these processes. We provide important normative data for future comparisons in pathology, where combining macro- and microvascular assessments may better help us prevent, stratify, and treat cerebrovascular disease.
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Affiliation(s)
- Kristina M. Zvolanek
- Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Biomedical Engineering, McCormick School of Engineering and Applied Sciences, Northwestern University, Evanston, IL, USA
| | - Jackson E. Moore
- Biomedical Engineering, McCormick School of Engineering and Applied Sciences, Northwestern University, Evanston, IL, USA
- Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Kelly Jarvis
- Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Sarah J. Moum
- Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Medical Imaging, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL, USA
| | - Molly G. Bright
- Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
- Biomedical Engineering, McCormick School of Engineering and Applied Sciences, Northwestern University, Evanston, IL, USA
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Shobade SO, Zabotina OA, Nilsen-Hamilton M. Plant root associated chitinases: structures and functions. FRONTIERS IN PLANT SCIENCE 2024; 15:1344142. [PMID: 38362446 PMCID: PMC10867124 DOI: 10.3389/fpls.2024.1344142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Accepted: 01/05/2024] [Indexed: 02/17/2024]
Abstract
Chitinases degrade chitin, a linear homopolymer of β-1,4-linked N-acetyl-D-glucosamine (GlcNAc) residues found in the cell walls of fungi and the exoskeletons of arthropods. They are secreted by the roots into the rhizosphere, a complex and dynamic environment where intense nutrient exchange occurs between plants and microbes. Here we modeled, expressed, purified, and characterized Zea mays and Oryza sativa root chitinases, and the chitinase of a symbiotic bacterium, Chitinophaga oryzae 1303 for their activities with chitin, di-, tri-, and tetra-saccharides and Aspergillus niger, with the goal of determining their role(s) in the rhizosphere and better understanding the molecular mechanisms underlying plant-microbe interactions. We show that Zea mays basic endochitinase (ZmChi19A) and Oryza sativa chitinase (OsChi19A) are from the GH19 chitinase family. The Chitinophaga oryzae 1303 chitinase (CspCh18A) belongs to the GH18 family. The three enzymes have similar apparent K M values of (20-40 µM) for the substrate 4-MU-GlcNAc3. They vary in their pH and temperature optima with OsChi19A activity optimal between pH 5-7 and 30-40°C while ZmChi19A and CspCh18A activities were optimal at pH 7-9 and 50-60°C. Modeling and site-directed mutation of ZmChi19A identified the catalytic cleft and the active residues E147 and E169 strategically positioned at ~8.6Å from each other in the folded protein. Cleavage of 4-MU-GlcNAc3 was unaffected by the absence of the CBD but diminished in the absence of the flexible C-terminal domain. However, unlike for the soluble substrate, the CBD and the newly identified flexible C-terminal domain were vital for inhibiting Aspergillus niger growth. The results are consistent with the involvement of the plant chitinases in defense against pathogens like fungi that have chitin exoskeletons. In summary, we have characterized the functional features and structural domains necessary for the activity of two plant root chitinases that are believed to be involved in plant defense and a bacterial chitinase that, along with the plant chitinases, may participate in nutrient recycling in the rhizosphere.
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Affiliation(s)
- Samuel O. Shobade
- Ames National Laboratory, U. S. Department of Energy, Ames, IA, United States
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, United States
| | - Olga A. Zabotina
- Ames National Laboratory, U. S. Department of Energy, Ames, IA, United States
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, United States
| | - Marit Nilsen-Hamilton
- Ames National Laboratory, U. S. Department of Energy, Ames, IA, United States
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, United States
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Li H, Lu Z, Hao MS, Kvammen A, Inman AR, Srivastava V, Bulone V, McKee LS. Family 92 carbohydrate-binding modules specific for β-1,6-glucans increase the thermostability of a bacterial chitinase. Biochimie 2023; 212:153-160. [PMID: 37121306 DOI: 10.1016/j.biochi.2023.04.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/30/2023] [Accepted: 04/28/2023] [Indexed: 05/02/2023]
Abstract
In biomass-processing industries there is a need for enzymes that can withstand high temperatures. Extensive research efforts have been dedicated to finding new thermostable enzymes as well as developing new means of stabilising existing enzymes. The attachment of a stable non-catalytic domain to an enzyme can, in some instances, protect a biocatalyst from thermal denaturation. Carbohydrate-binding modules (CBMs) are non-catalytic domains typically found appended to biomass-degrading or modifying enzymes, such as glycoside hydrolases (GHs). Most often, CBMs interact with the same polysaccharide as their enzyme partners, leading to an enhanced reaction rate via the promotion of enzyme-substrate interactions. Contradictory to this general concept, we show an example of a chitin-degrading enzyme from GH family 18 that is appended to two CBM domains from family 92, both of which bind preferentially to the non-substrate polysaccharide β-1,6-glucan. During chitin hydrolysis, the CBMs do not contribute to enzyme-substrate interactions but instead confer a 10-15 °C increase in enzyme thermal stability. We propose that CBM92 domains may have a natural enzyme stabilisation role in some cases, which may be relevant to enzyme design for high-temperature applications in biorefinery.
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Affiliation(s)
- He Li
- Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, 106 91, Stockholm, Sweden
| | - Zijia Lu
- Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, 106 91, Stockholm, Sweden
| | - Meng-Shu Hao
- Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, 106 91, Stockholm, Sweden
| | - Alma Kvammen
- Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, 106 91, Stockholm, Sweden
| | - Annie R Inman
- Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, 106 91, Stockholm, Sweden
| | - Vaibhav Srivastava
- Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, 106 91, Stockholm, Sweden
| | - Vincent Bulone
- Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, 106 91, Stockholm, Sweden; College of Medicine & Public Health, Flinders University, Bedford Park Campus, Sturt Road, SA, 5042, Australia
| | - Lauren S McKee
- Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, 106 91, Stockholm, Sweden; Wallenberg Wood Science Center, Teknikringen 56-58, 100 44, Stockholm, Sweden.
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Metagenomic Approaches as a Tool to Unravel Promising Biocatalysts from Natural Resources: Soil and Water. Catalysts 2022. [DOI: 10.3390/catal12040385] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Natural resources are considered a promising source of microorganisms responsible for producing biocatalysts with great relevance in several industrial areas. However, a significant fraction of the environmental microorganisms remains unknown or unexploited due to the limitations associated with their cultivation in the laboratory through classical techniques. Metagenomics has emerged as an innovative and strategic approach to explore these unculturable microorganisms through the analysis of DNA extracted from environmental samples. In this review, a detailed discussion is presented on the application of metagenomics to unravel the biotechnological potential of natural resources for the discovery of promising biocatalysts. An extensive bibliographic survey was carried out between 2010 and 2021, covering diverse metagenomic studies using soil and/or water samples from different types and locations. The review comprises, for the first time, an overview of the worldwide metagenomic studies performed in soil and water and provides a complete and global vision of the enzyme diversity associated with each specific environment.
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Mohd Afandi NS, Habib MAH, Ismail MN. Recent insights on gene expression studies on Hevea Brasiliensis fatal leaf fall diseases. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2022; 28:471-484. [PMID: 35400887 PMCID: PMC8943083 DOI: 10.1007/s12298-022-01145-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 01/24/2022] [Accepted: 01/27/2022] [Indexed: 06/14/2023]
Abstract
Hevea brasiliensis is one of the most important agricultural commodities globally, heavily cultivated in Southeast Asia. Fatal leaf fall diseases cause aggressive leaf defoliation, linked to lower latex yield and death of crops before maturity. Due to the significant consequences of the disease to H. brasiliensis, the recent gene expression studies from four fall leaf diseases of H. brasiliensis were gathered; South American leaf blight, powdery mildew, Corynespora cassiicola and Phytophthora leaf fall disease. The differential analysis observed the pattern of commonly expressed genes upon fungi triggers using RT-PCR, DDRT-PCR, Real-time qRT-PCR and RNA-Seq. We have observed that RNA-Seq is the best tool to seek novel genes. Among the identified genes with defence-against fungi were pathogenesis-related genes such as β-1,3-glucanase and chitinase, the reactive oxygen species, and the phytoalexin biosynthesis. This manuscript also provided functional elaboration on the responsive genes and predicted possible biosynthetic pathways to identify and characterise novel genes in the future. At the end of the manuscript, the PCR methods and proteomic approaches were presented for future molecular and biochemical studies in the related diseases to H. brasiliensis.
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Affiliation(s)
- Nur Syafiqah Mohd Afandi
- Analytical Biochemistry Research Centre, Universiti Sains Malaysia, 11900 Bayan Lepas, Penang, Malaysia
| | - Mohd Afiq Hazlami Habib
- Analytical Biochemistry Research Centre, Universiti Sains Malaysia, 11900 Bayan Lepas, Penang, Malaysia
| | - Mohd Nazri Ismail
- Analytical Biochemistry Research Centre, Universiti Sains Malaysia, 11900 Bayan Lepas, Penang, Malaysia
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 USM Penang, Malaysia
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Aiysha D, Latif Z. Assessing hydrolytic enzyme production ability of bacterial strains from bovine manure as potential biowaste conversion candidates. J Basic Microbiol 2021; 62:116-123. [DOI: 10.1002/jobm.202100294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 10/10/2021] [Accepted: 11/20/2021] [Indexed: 11/10/2022]
Affiliation(s)
- Dalaq Aiysha
- Institute of Microbiology and Molecular Genetics, Faculty of Life Sciences, Quaid‐i‐Azam Campus University of the Punjab Lahore Pakistan
| | - Zakia Latif
- Institute of Microbiology and Molecular Genetics, Faculty of Life Sciences, Quaid‐i‐Azam Campus University of the Punjab Lahore Pakistan
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Dai Y, Yang F, Liu X, Wang H. The discovery and characterization of a novel chitinase with dual catalytic domains from a Qinghai-Tibetan Plateau wetland soil metagenome. Int J Biol Macromol 2021; 188:482-490. [PMID: 34331981 DOI: 10.1016/j.ijbiomac.2021.07.153] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 07/12/2021] [Accepted: 07/22/2021] [Indexed: 10/20/2022]
Abstract
A novel chitinase (P1724) was discovered from a Qinghai-Tibetan plateau microbial metagenome. P1724 contains two GH18 family catalytic domains and is phylogenetically distant from any of the chitinases studied. P1724 and its truncated versions, P1724(∆cGH18) and P1724(∆nGH18), were produced in Escherichia coli and characterized. Using colloidal chitin as substrate, the three recombinant proteins showed maximum hydrolytic activities at 40 °C, pH 5.0-6.0 and 0-0.5 M NaCl, and were cold adaptive, as they remained active at 4 °C; their chitinase activities were decreased with the presence of Cu2+ and EDTA, but increased with Ba2+ and Ca2+; they all showed both chitobiosidase and endochitinase activities. Compared to P1724(∆nGH18), P1724 and P1724(∆cGH18) shared more similarities in temperature and pH stabilities, NaCl tolerance, and substrate affinity, suggesting the N-terminal GH18 domain contributed more than the C-terminal GH18 did in biochemical characteristics of P1724. kcat/Km value of P1724 was significantly higher than the sum values of P1724(∆cGH18) and P1724(∆nGH18), which indicated that two GH18 domains of P1724 worked cooperatively in degrading chitin. This study has not only broadened the understanding of unknown chitinases in nature but also discussed the strategy of adding additional catalytic domains in enzyme engineering.
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Affiliation(s)
- Yumei Dai
- College of Animal Science and Technology, Hebei Normal University of Science &Technology, Qinhuangdao 066600, PR China; Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China.
| | - Feng Yang
- Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Xiao Liu
- College of Life Sciences, Sichuan Normal University, Chengdu 610101, PR China
| | - Hongling Wang
- College of Life Sciences, Sichuan Normal University, Chengdu 610101, PR China
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8
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Tuna HI, Alparslan GB. Effects of Orem's Self-Care Model of Nursing on Hand Symptoms and Life Activities in Geriatric Individuals Diagnosed with Rheumatoid Arthritis: A Pilot Study. Res Theory Nurs Pract 2021; 35:RTNP-D-20-00093. [PMID: 33827916 DOI: 10.1891/rtnp-d-20-00093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND AND PURPOSE According to Orem's self-care deficit theory, when patients cannot meet their care needs, they need nursing systems for maintaining their health. Nursing care for elderly patients with rheumatoid arthritis (RA) should be based on maintaining self-care. This study aims to determine the effects of Orem's self-care model of nursing care given to geriatric patients with RA on hand symptoms, life activities, and hand pain. METHODS The study sample comprised a total of 22 patients (intervention group, 11; control group, 11) who met the sample selection criteria at a rheumatology outpatient clinic of a university hospital between June 17, 2019 and September 20, 2019. All interviews with patients in the intervention group were conducted by daily phone calls and a face-to-face interview at the hospital every 4 weeks. Patients continued to receive routine prescription by a physician during the course of application. RESULTS No difference was observed between the groups in terms of descriptive patient characteristics (p > .05). Hand pain, hand symptoms, and life activities of patients in the intervention group were measured at study initiation, week 4, and week 8. Intragroup comparison revealed that hand pain, hand symptoms, and life activity scores were lowest at week 8 in the intervention group (p < .05). IMPLICATIONS FOR PRACTICE This study indicates that nursing care given according to Orem's self-care model is effective in reducing pain, improving hand functions, and performing life activities.
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Recent advances in the bioprospection and applications of chitinolytic bacteria for valorization of waste chitin. Arch Microbiol 2021; 203:1953-1969. [PMID: 33710379 DOI: 10.1007/s00203-021-02234-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 01/12/2021] [Accepted: 02/11/2021] [Indexed: 10/21/2022]
Abstract
One of the most abundant natural polymers on earth, chitin is a fibrous and structural polysaccharide, composed of N-acetyl-D-glucosamine. The biopolymer is the major structural constituent of fungi, arthropods, mollusks, nematodes, and some algae. The biodegradation of chitin is largely manifested by chitinolytic enzyme secreting organisms including bacteria, insects, and plants. Among them, bacterial chitinases represent the most promising, inexpensive, and sustainable source of proteins that can be employed for industrial-scale applications. To this end, the presented review comes at a timely moment to highlight the major sources of chitinolytic bacteria. It also discusses the potential pros and cons of prospecting bacterial chitinases that can be easily manipulated through genetic engineering. Additionally, we have elaborated the recent applications of the chitin thereby branding chitinases as potential candidates for biorefinery and biomedical research for eco-friendly and sustainable management of chitin waste in the environment.
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10
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Li RK, Hu YJ, Ng TB, Guo BQ, Zhou ZH, Zhao J, Ye XY. Expression and biochemical characterization of a novel chitinase ChiT-7 from the metagenome in the soil of a mangrove tidal flat in China. Int J Biol Macromol 2020; 158:1125-1134. [PMID: 32360969 DOI: 10.1016/j.ijbiomac.2020.04.242] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 04/25/2020] [Accepted: 04/27/2020] [Indexed: 12/18/2022]
Abstract
Chitinases play an important role in the process of chitin bioavailability. In this study, we cloned a new chitinase gene and characterized its recombinant protein. The new 1251 bp gene of chitinase (ChiT-7) was cloned from the metagenome of the mangrove tidal flat soil in the city of Zhangzhou in Fujian Province (China) by genome walking. The gene encoded a mature protein with 381 amino acids, which manifested certain sequence similarity (59% identity) to characterized GH18 chitinases. The mature protein of ChiT-7 was successfully expressed in E. coli BL21 (DE3). After purification, the specific activity of the recombinant enzyme was 0.63 U/mg at the optimal pH of 6.0 and the optimal temperature of 45 °C. The rChiT-7 was active over a wide pH range, and the residual enzyme activity reached 80% or higher at 30 °C-50 °C. rChiT-7 hydrolyzed colloidal chitin with (GlcNAc)2 and GlcNAc as the main final products. Structural analysis of ChiT-7 indicated that ChiT-7 could be a processive chitinase. rChiT-7 manifested characteristics analogous to those of fungi and actinomycetes and exhibited sequence homology.
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Affiliation(s)
- Ren Kuan Li
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China; National Engineering Laboratory for High-efficient Enzyme Expression, PR China
| | - Ya Juan Hu
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China
| | - Tzi Bun Ng
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Bing Qi Guo
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China
| | - Zi He Zhou
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China
| | - Jing Zhao
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China
| | - Xiu Yun Ye
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China; National Engineering Laboratory for High-efficient Enzyme Expression, PR China.
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11
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Anticoagulant activity of partially purified chitinase produced by Citrobacter freundii str. nov. haritD11 by fermentation of wheat bran coupled with fish scales. SN APPLIED SCIENCES 2018. [DOI: 10.1007/s42452-018-0097-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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12
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Oyeleye A, Normi YM. Chitinase: diversity, limitations, and trends in engineering for suitable applications. Biosci Rep 2018; 38:BSR2018032300. [PMID: 30042170 PMCID: PMC6131217 DOI: 10.1042/bsr20180323] [Citation(s) in RCA: 121] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 06/07/2018] [Accepted: 12/07/2018] [Indexed: 01/09/2023] Open
Abstract
Chitinases catalyze the degradation of chitin, a ubiquitous polymer generated from the cell walls of fungi, shells of crustaceans, and cuticles of insects. They are gaining increasing attention in medicine, agriculture, food and drug industries, and environmental management. Their roles in the degradation of chitin for the production of industrially useful products and in the control of fungal pathogens and insect pests render them attractive for such purposes. However, chitinases have diverse sources, characteristics, and mechanisms of action that seem to restrain optimization procedures and render standardization techniques for enhanced practical applications complex. Hence, results of laboratory trials are not usually consistent with real-life applications. With the growing field of protein engineering, these complexities can be overcome by modifying or redesigning chitinases to enhance specific features required for specific applications. In this review, the variations in features and mechanisms of chitinases that limit their exploitation in biotechnological applications are compiled. Recent attempts to engineer chitinases for improved efficiency are also highlighted.
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Affiliation(s)
- Ayokunmi Oyeleye
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Malaysia
- Enzyme and Microbial Technology Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Malaysia
| | - Yahaya M Normi
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Malaysia
- Enzyme and Microbial Technology Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Malaysia
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Alves TB, de Oliveira Ornela PH, de Oliveira AHC, Jorge JA, Guimarães LHS. Production and characterization of a thermostable antifungal chitinase secreted by the filamentous fungus Aspergillus niveus under submerged fermentation. 3 Biotech 2018; 8:369. [PMID: 30105194 DOI: 10.1007/s13205-018-1397-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 08/07/2018] [Indexed: 12/23/2022] Open
Abstract
The filamentous fungus Aspergillus niveus produced extracellular antifungal chitinase when cultured under submerged fermentation (SbmF) using crab shells as the carbon source. Maximal chitinase production was achieved at 192 h of cultivation using minimal medium containing 1% chitin. The enzyme was purified 1.97-fold with 40% recovery by ammonium sulfate precipitation and Sephadex G-100 gel filtration. The molecular mass was estimated to be 44 kDa by both 12% SDS-PAGE and Sepharose CL-6B gel filtration. Maximal A. niveus chitinase activity was obtained at 65 °C and pH 5.0. The enzyme was fully stable at 60 °C for up to 120 min and the enzymatic activity was increased by Mn2+. In the presence of reducing and denaturing compounds, the enzyme activity was not drastically affected. The chitinase was able to hydrolyze colloidal chitin, azure chitin, and 4-nitrophenyl N-acetyl-β-D glucosaminide; for the latter, the K0.5 and maximal velocity (Vmax) were 3.51 mM and 9.68 U/mg of protein, respectively. The A. niveus chitinase presented antifungal activity against Aspergillus niger (MIC = 84 µg/mL), A. fumigatus (MIC = 21 µg/mL), A. flavus (MIC = 24 µg/mL), A. phoenicis (MIC = 24 µg/mL), and Paecilomyces variotii (MIC = 21 µg/mL). The fungus A. niveus was able to produce a thermostable and denaturation-resistant chitinase able to inhibit fungal development, signaling its biotechnological potential.
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Microbial and viral chitinases: Attractive biopesticides for integrated pest management. Biotechnol Adv 2018; 36:818-838. [DOI: 10.1016/j.biotechadv.2018.01.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 12/28/2017] [Accepted: 01/02/2018] [Indexed: 02/01/2023]
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15
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Purohit A, Rai SK, Chownk M, Sangwan RS, Yadav SK. Xylanase from Acinetobacter pittii MASK 25 and developed magnetic cross-linked xylanase aggregate produce predominantly xylopentose and xylohexose from agro biomass. BIORESOURCE TECHNOLOGY 2017; 244:793-799. [PMID: 28822953 DOI: 10.1016/j.biortech.2017.08.034] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 08/05/2017] [Accepted: 08/07/2017] [Indexed: 06/07/2023]
Abstract
Most of the chemical and biochemical processes used for the de-polymerization of structural polymers of lignocellulosic biomass are environment unfriendly and costly. Here an efficient process based on xylanase, produced by Acinetobacter pittii MASK25 (MTCC 25132), hydrolysis of only physically treated rice straw and corn cob has been developed for the production of xylooligosaccharides. Bacterial strain isolated from soil was found to produce maximum xylanase at 30°C and pH 7. While the optimum temperature and pH of xylanase were characterized as 40°C and 5. Process was further improved by developing magnetic-xylanase CLEA. Crude xylanase and magnetic-xylanase CLEA could convert respectively more than 45% and 60% xylan of the powdered rice straw and corn cob into xylooligosaccharides. Interestingly, hydrolysis by both types of enzymatic forms was found to produce predominantly xylopentose and xylohexose. Hence, the process is environment friendly and the predominant production of xylopentose and xylohexose could find unique prebiotic applications.
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Affiliation(s)
- Anjali Purohit
- Biotechnology and Synthetic Biology, Center of Innovative and Applied Bioprocessing, Knowledge City, Sector-81, Mohali 140306, India
| | - Shushil Kumar Rai
- Biotechnology and Synthetic Biology, Center of Innovative and Applied Bioprocessing, Knowledge City, Sector-81, Mohali 140306, India
| | - Manisha Chownk
- Biotechnology and Synthetic Biology, Center of Innovative and Applied Bioprocessing, Knowledge City, Sector-81, Mohali 140306, India
| | - Rajender Singh Sangwan
- Biotechnology and Synthetic Biology, Center of Innovative and Applied Bioprocessing, Knowledge City, Sector-81, Mohali 140306, India
| | - Sudesh Kumar Yadav
- Biotechnology and Synthetic Biology, Center of Innovative and Applied Bioprocessing, Knowledge City, Sector-81, Mohali 140306, India.
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Berini F, Casciello C, Marcone GL, Marinelli F. Metagenomics: novel enzymes from non-culturable microbes. FEMS Microbiol Lett 2017; 364:4329276. [DOI: 10.1093/femsle/fnx211] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 10/02/2017] [Indexed: 01/02/2023] Open
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