Optimization of cultural conditions for the production of antifungal chitinase by Streptomyces sporovirgulis

Actinomycetes were screened from soil in the centre of Poland on chitin medium. Amongst 30 isolated strains one with high activity of chitinase was selected. It was identified as Streptomyces sporovirgulis. Chitinase activity was detected from the second day of cultivation, then increased gradually and reached maximum after 4 days. The maximum chitinase production was observed at pH 8.0 and 25–30°C in the medium with sodium caseinate and asparagine as carbon and nitrogen sources and with shrimp shell waste as inducer of enzyme. Chitinase of S. sporovirgulis was purified from a culture medium by fractionation with ammonium sulphate as well as by chitin affinity chromatography. The molecular weight of the enzyme was 27 kDa. The optimum temperature and pH for the chitinase were 40°C and pH 8.0. The enzyme activity was characterised by high stability at the temperatures between 35 and 40°C after 240 min of preincubation. The activity of the enzyme was strongly inhibited in the presence of Pb²⁺, Hg²⁺ and stabilized by the ions Mg²⁺. Purified chitinase from S. sporovirgulis inhibited growth of fungal phytopathogen Alternaria alternata. Additionally, the crude chitinase inhibited the growth of potential phytopathogens such as Penicillium purpurogenum and Penillium sp.     

Cloning and Expression of a Novel Chitinase chi58 from Chaetomium cupreum in Pichia pastoris

A gene encoding a novel chitinase chi58 was cloned from the fungus Chaetomium cupreum by using inverse PCR. The DNA sequence of chi58 contains a 1,602 bp open reading frame and two introns that are 52 and 201 bp in length. Regarding our in silico analysis, chi58 is a modular enzyme composed of a family-18 catalytic domain, which is responsible for chitinase activity, and a chitin-binding domain containing several cysteines. Apparently, the function of these domains is to anchor the enzyme tightly onto the large insoluble polymeric substrate. Chi58 has a pI of 4.47 and a deduced molecular mass of 58 kDa. The optimal pH and temperature conditions were determined to be 5.8 and 45°C, respectively, when colloidal chitin was used as the substrate. SDS-PAGE and zymogram analyses indicated the presence of a single active chitinase. Cells with pPIC9K-chi58 produced an extracellular chitinase that had an activity of 39 U/ml protein. Metal ions such as Ba²⁺, Mg²⁺, K⁺, Cu²⁺, Fe³⁺, Zn²⁺, and Co²⁺ also influenced the activity of the recombinant enzyme.     

Production of Antifungal Chitinase by Aspergillus niger LOCK 62 and Its Potential Role in the Biological Control

Aspergillus niger LOCK 62 produces an antifungal chitinase. Different sources of chitin in the medium were used to test the production of the chitinase. Chitinase production was most effective when colloidal chitin and shrimp shell were used as substrates. The optimum incubation period for chitinase production by Aspergillus niger LOCK 62 was 6?days. The chitinase was purified from the culture medium by fractionation with ammonium sulfate and affinity chromatography. The molecular mass of the purified enzyme was 43?kDa. The highest activity was obtained at 40?°C for both crude and purified enzymes. The crude chitinase activity was stable during 180?min incubation at 40?°C, but purified chitinase lost about 25?% of its activity under these conditions. Optimal pH for chitinase activity was pH 6–6.5. The activity of crude and purified enzyme was stabilized by Mg²⁺ and Ca²⁺ ions, but inhibited by Hg²⁺ and Pb²⁺ ions. Chitinase isolated from Aspergillus niger LOCK 62 inhibited the growth of the fungal phytopathogens: Fusarium culmorum, Fusarium solani and Rhizoctonia solani. The growth of Botrytis cinerea, Alternaria alternata, and Fusarium oxysporum was not affected.     

Characterization of β-N-acetylglucosaminidase from a marine Pseudoalteromonas sp. for application in N-acetyl-glucosamine production

The psychrotolerant Pseudoalteromonas issachenkonii PAMC 22718 was isolated for its high exo-acting chitinase activity in the Kara Sea, Arctic. An exo-acting chitinase (W-Chi22718) was homogeneously purified from the culture supernatant of PAMC 22718, the molecular weight of which was estimated to be approximately 112?kDa. Due to its β-N-acetylglucosaminidase activity, W-Chi22718 was able to produce N-acetyl-D-glucosamine (GlcNAc) monomers from chitin oligosaccharide substrates. W-Chi22718 displayed chitinase activity from 0 to 37°C (optimal temperature of 30°C) and maintained activity from pH 6.0 to 9.0 (optimal pH of 7.6). W-Chi22718 exhibited a relative activity of 13 and 35% of maximal activity at 0 and 10°C, respectively, which is comparable to the activities of previously characterized, cold-adapted bacterial chitinases. W-Chi22718 activity was enhanced by K⁺, Ca²⁺, and Fe²⁺, but completely inhibited by Cu²⁺ and SDS. We found that W-Chi22718 can produce much more (GlcNAcs) from colloidal chitin, working together with previously characterized cold-active endochitinase W-Chi21702. Genome sequencing revealed that the corresponding gene (chi22718_IV) was 2,856?bp encoding a 951?amino acid protein with a calculated molecular weight of approximately 102?kDa.     

Purification and Characteristics of an Autolytic Chitinase of Piromyces communis OTS1 from Culture Medium

An autolysis chitinase was purified from the cultural medium of the anaerobic fungus Piromyces communis OTS1 by ammonium sulfate precipitation, affinity chromatography with regenerated chitin, chromato-focusing, gel filtration, and chromato-focusing again. The optimal pH and temperature were 6.0 and 50°C, respectively, for a 20-min assay. The chitinase was stable from pH 6.0 to 8.0, but was unstable at 70°C for 20 min. The molecular mass of chitinase was estimated by SDS-PAGE to be 44.9 kDa, and its pI was 4.4. The enzyme activity, which was of the ‘endo’ type, was inhibited by Hg²⁺ and allosamidin. The chitinase hydrolyzes chitin powder and fungal cell walls at a higher rate than an artificial chitin substrate. It can be concluded that extracellular chitinase is similar to cytosolic chitinase, but they are not the same protein. Received: 3 December 1996 / Accepted: 28 January 1997     

Purification and properties of chitinase from Streptomyces cinereoruber

A chitinase (EC 3.2.1.14) was purified from the culture filtrate of Streptomyces cinereoruber, selected as a microorganism which produces enzymes lysing Aspergillus niger cell wall, by fractional precipitation with ammonium sulfate and column chromatographies on DEAE-cellulose, Sephadex G-100 and CM-Sephadex C-50. The final preparation was homogenous in polyacrylamide gel disc electrophoresis. The molecular weight of the enzyme was about 19,000 daltons and its isoelectric point was pH 8.6. The optimum pH and temperature for chitinase activity were 4.5 and at 50°C, respectively. The enzyme was stable in the pH range from 4.0 to 10.0. The activity was inhibited by Ag⁺, Hg⁺, Hg²⁺ and p-chloromercuribenzoate. Paper chromatographic analysis demonstrated that the hydrolytic products of colloidal chitin and chitotriose with the enzyme were N-acetylglucosamine and chitobiose. The lysis of A. niger cell wall with the enzyme is discussed.     

Cloning of the 52-kDa chitinase gene from Serratia marcescens KCTC2172 and its proteolytic cleavage into an active 35-kDa enzyme

A chitinase gene (pCHI52) encoding the 52-kDa chitinase was isolated from a Serratia marcescens KCTC2172 cosmid library. This chitinase gene consists of 2526 bp with an open reading frame that encodes 485 amino acids. Escherichia coli harboring the pCHI52 gene secreted not only a 52-kDa but also a 35-kDa chitinase into the culture supernatant. We purified both 52-kDa and 35-kDa chitinases using a chitin affinity column and Sephacryl-S-300 gel filtration chromatography. We determined that the 17 N-terminal amino acid sequences of the 52-kDa and the 35-kDa chitinase are identical. Furthermore, a protease obtained from S. marcescens KCTC2172 cleaved the 52-kDa chitinase into the 35-kDa protein with chitinase activity. These results suggest that the 35-kDa chitinase derives from the 52-kDa chitinase by post-translational proteolytic modification. The optimal reaction temperature of 45°C and the optimal pH of 5.5 were identical for both enzymes. The specific activities of the 52-kDa and 35-kDa chitinases on natural swollen chitin were 67 μmol min⁻¹ mg⁻¹ and 60 μmol min⁻¹ mg⁻¹, respectively.     

PARTIAL PURIFICATION,CHARACTERIZATION, AND KINETIC STUDIES OF A LOW-MOLECULAR-WEIGHT,ALKALI-TOLERANT CHITINASE ENZYME FROM Bacillus subtilis JN032305, A POTENTIAL BIOCONTROL STRAIN

A new alkalophilic low-molecular-mass chitinase of 14 kD from the potent biocontrol agent Bacillus subtilis JN032305 was partially purified and enzymology of the chitinase was studied. The enzyme showed optimal pH of 9.0 and temperature of 50°C. The enzyme was found stable during the 60-min incubation at 50°C. The chitinase was inhibited by group specific agents like IAA, DAN, TLCK, and SDS and metal ions Mg²⁺, Ca²⁺, Fe²⁺, Mn²⁺, Ba²⁺, and Hg²⁺, whereas Zn²⁺ did not show significant inhibitory effect against the chitinase. PMSF partially inhibited the enzyme. Substrates specificity tests indicated that the enzyme showed 75% of relative activity on glycol chitin, 58% on carboxymethylcellulose (CMC), 33% on chitin flakes, and 166% laminarin compared to that on colloidal chitin. The enzyme also hydrolyzed 4-methylumbelliferyl-N-acetyl-D-glucosaminide, indicating its chitobiase activity. The chitinase of this study has broad specificity, which could hydrolyze not only the glycosidic bond in GlcNAc–GlcNAc but also that of related carbohydrates with glycosidic linkages. The partially purified chitinase not only showed antifungal activity against Rhizoctonia solani and Colletotrichum gloeosporioides, two potent phytopathogens of chilli, but also increased the germination of chilli seeds when infected with the two potent phytopathogenic fungi.     

Effects of dehydration and low temperatures on the oxidation of high-potential cytochrome c by photosynthetic reaction centers in Ectothiorhodospira shaposhnikovii

Effects of temperature and dehydration on the efficiency of electron transfer from membrane-bound high-potential cytochromes c_h to the reaction-center bacteriochlorophyll (P-890) in Ectothiorhodospira shaposhnikovii have been studied. A kinetic analysis of the cytochrome oxidation suggests that there are at least two conformational states of the c_h-P-890 complex, of which only one allows photoinduced electron transfer from cytochrome to P-890⁺. Lowering the temperature of dehydration leads to a change in the proportion of the populations in the two conformations. The observed 2-fold deceleration of cytochrome oxidation can be related only to the diminution of the amount of photoactive cytochromes per reaction center. The rate constant for the transfer of an electron from cytochrome c_h to bacteriochlorophyll is 2.8 · 10⁵ s⁻¹ and is independent of temperature and dehydration (as estimated within the accuracy of the experiments). The effects produced by low temperature and dehydration are completely reversible. The thermodynamic parameters of the transition of the cytochrome from the nontransfer to electron-transfer conformation were estimated. For room temperature (+ 20°C) in chromatophore preparations, ΔG = −5.4 kJ · M⁻¹, ΔH = 60 kJ · M⁻¹, ΔS = 0.22 kJ · M⁻¹ · K⁻¹. For Triton X-100 subchromatophore preparations, the absolute values of the above parameters are significantly lower: ΔG = −2.8 kJ · M⁻¹, ΔH = 18 kJ · M⁻¹, and ΔS = 0.075 kJ · M⁻¹ · K⁻¹. To a larger extent, the above parameters are diminished for chromatophore preparations in an 80% glycerol solution: ΔG = −1.7 kJ · M⁻¹, ΔH = 6 kJ · M⁻¹, ΔS = 0.025 kJ · M⁻¹ · K⁻¹. The data suggest the hydrophobic character of the forces that maintain the P-890-c_h complex in the electron-transfer conformation. The results obtained suggest that electron tunneling within the complex cannot occur until a specific conformational configuration of the complex is formed. The efficiency of cytochrome c_h oxidation is determined by the temperature, the degree of dehydration and the environmental conditions, whereas the transfer of an electron itself in the electron-transfer configuration is essentially independent of temperature and hydration.     

Characteristics of cold-adaptive endochitinase from Antarctic bacterium Sanguibacter antarcticus KOPRI 21702

The psychrotrophic Sanguibacter antarcticus KOPRI 21702^T, isolated from Antarctic seawater, produced a cold-adapted chitinolytic enzyme that is a new 55 kDa family 18 chitinase (Chi21702). Chi21702 exhibited high activities toward pNP-(GlcNAc)₂ and pNP-(GlcNAc)₃ with no activity for pNP-GlcNAc, indicating that it prefers chitin chains longer than dimers, just as endochitinases do. A mixture of GlcNAc and GlcNAc₂ was produced as a main product by Chi21702 activity from chitin oligosaccharides and swollen chitin, while less GlcNAc₃ was produced. These results show that Chi21702 has an endochitinase activity, randomly hydrolyzing chitin at internal sites. Chi21702 displayed chitinase activity at 0–40 °C (optimal temperature of 37 °C), maintained its activity at pH 4–11 (optimal pH of 7.6). Interestingly, Chi21702 exhibited relative activities of 40% and 60% at 0 and 10 °C, respectively, in comparison to 100% at 37 °C, which is higher than those of the previously characterized, cold-adapted, chitinases from bacterial strains.     

Studies on pH and thermal stability of novel purified L-asparaginase from <Emphasis Type="Italic">Pectobacterium carotovorum</Emphasis> MTCC 1428

Glutaminase free L-asparaginase is known to be an excellent anticancer agent. In the present study, the combined effect of pH and temperature on the performance of purified novel L-asparaginase from Pectobacterium carotovorum MTCC 1428 was studied under assay conditions using response surface methodology (RSM). Deactivation studies and thermodynamic parameters of this therapeutically important enzyme were also investigated. The optimum pH and temperature of the purified L-asparaginase were found to be 8.49 and 39.3°C, respectively. The minimum deactivation rate constant (k _d ) and maximum half life (t _1/2) were found to be 0.041 min⁻¹ and 16.9 h, respectively at pH of 8.6 and 40°C. Thermodynamic parameters (ΔG, ΔH, ΔS, and activation energies) were also evaluated for purified L-asparaginase. The probable mechanism of deactivation of purified L-asparaginase was explained to an extent on the basis of deactivation studies and thermodynamic parameters.     

Purification and characterization of aβ-galactosidase fromTreponema phagedenis (Reiter strain)

A β-galactosidase was highly purified from a cellular extract ofTreponema phagedenis (Reiter strain) by ammonium sulfate precipitation and successive chromatography on Sepharose 6B and DEAE-Sephadex. The purified enzyme was homogeneous in SDS-polyacrylamide gel electrophoresis. The molecular weight estimated was 580,000. The optimal pH, ionic strength, and temperature were 6.5, 0.1, and 50°C, respecitvely. The enzyme was stable only at around pH 6.5 and at temperatures lower than 35°C. The enzyme was irreversibly inhibited byp-chloromercuribenzoate and divalent cations such as Hg²⁺, Cu²⁺, Zn²⁺, Cd²⁺, and Pb²⁺. The Km values forp-nitrophenyl-β-D-galactopyranoside,o-nitrophenyl-β-D-galactopyranoside, and lactose were 0.29, 0.36, and 5.4 mM, respectively.     

Analysis of histone messenger RNA of Drosophila melanogaster by two-dimensional gel electrophoresis.

The kinetics of the hydrogen-deuterium exchange reactions of double-helical poly (rI) · poly (rC), single-stranded poly(rC) and poly(rI), inosine, and cytosine- 5′-phosphoric acid have been examined, at various temperatures in the range 20 °C to 52 °C, by stopped-flow ultraviolet spectrophotometry, in the region 270 to 300 nm. For the solution of double-helical poly(rI) · poly(rC), two first-order deuteration reactions were found: a fast one and a slow one. At 25 °C and at pH 7.0, the rate constant was 12.3 s^?1 for the fast reaction, and 0.13 s^?1 for the slow reaction. The rate constant of the fast reaction is nearly equal to that of the single-stranded poly(rC) (12.6 s^?1), and is assigned to the deuteration at the amino hydrogen (that is, free from the C · I hydrogen bond) of the cytosine residue. The slow reaction is attributable to the deuteration of the two hydrogens: the amino hydrogen of rC and imide hydrogen of rI, which are rapidly exchanging with each other within every rC · rI base-pair. From the observed temperature effect on this slow reaction rate, it has been concluded that there are two types of “opening process” that are relevant to the hydrogen exchange reaction; one of them is predominent in the range 47 °C to 52 °C and the other in the temperature region lower than 47 °C. The enthalpy (H) and entropy (S) differences of the “open” and “closed” forms in the former type process are ΔH = 167 kcal per mole and ΔS = 507 e.u., while in the latter ΔH = 8.1 kcal per mole and ΔS = 10 e.u..     

Characterization of Chitinase Produced by the Alkaliphilic <Emphasis Type="Italic">Bacillus mannanilyticus</Emphasis> IB-OR17 B1 Strain

The paper reports on the isolation of an extracellular chitinase produced by the alkaliphilic Bacillus mannanilyticus IB-OR17 B1 strain grown in media containing crab shell and bee chitin at a pH of 8–11. The enzyme was 860-fold purified by ultrafiltration and chitin sorption. The molecular weight of the purified chitinase was shown by denaturing electrophoresis to be 56 kDa. The enzyme showed maximum activity at a pH of 7.5–8.0 and 65°C and was stable within a pH range of 3.5–10.5 and temperature range of 75–85°C. With colloidal chitin as substrate, the kinetic characteristics of the chitinase were determined as follows: K_M ~ 1.32 mg/mL and V_max ~ 5.05 μM min^–1. N-acetyl-D-glucosamine and its dimer were the main products of enzymatic chitin cleavage, while the trisaccharide was detected just in minor quantities. The chitinase actively hydrolyzed p-nitrophenyl-GlcNAc₂ according to the exo-mechanism of substrate hydrolysis characteristic of chitobiosidases.     

Chitinase production by a newly isolated thermotolerant Paenibacillus sp. BISR-047

Chitinase is one of the important mycolytic enzymes with industrial significance, and is produced by a number of organisms, including bacteria. In this study, we describe isolation, characterization and media optimization for chitinase production from a newly isolated thermotolerant bacterial strain, BISR-047, isolated from desert soil and later identified as Paenibacillus sp. The production of extracellularly secreted chitinase by this strain was optimized by varying pH, temperature, incubation period, substrate concentrations, carbon and nitrogen source,etc. The maximum chitinase production was achieved at 45 °C with media containing (in g/l) chitin 2.0, yeast extract 1.5, glycerol 1.0, and ammonium sulphate 0.2 % (media pH 7.0). A three-fold increase in the chitinase production (712 IU/ml) was found at the optimized media conditions at 6 days of incubation. The enzyme showed activity at broad pH (3–10) and temperature (35–100 °C) ranges, with optimal activity displayed at pH 5.0 and 55 °C, respectively. The produced enzyme was found to be highly thermostable at higher temperatures, with a half-life of 4 h at 100 °C.     

Chitinase production by <Emphasis Type="Italic">Bacillus thuringiensis</Emphasis> and <Emphasis Type="Italic">Bacillus licheniformis</Emphasis>: Their potential in antifungal biocontrol

Thirty bacterial strains were isolated from the rhizosphere of plants collected from Egypt and screened for production of chitinase enzymes. Bacillus thuringiensis NM101-19 and Bacillus licheniformis NM120-17 had the highest chitinolytic activities amongst those investigated. The production of chitinase by B. thuringiensis and B. licheniformis was optimized using colloidal chitin medium amended with 1.5% colloidal chitin, with casein as a nitrogen source, at 30°C after five days of incubation. An enhancement of chitinase production by the two species was observed by addition of sugar substances and dried fungal mats to the colloidal chitin media. The optimal conditions for chitinase activity by B. thuringiensis and B. licheniformis were at 40°C, pH 7.0 and pH 8.0, respectively. Na⁺, Mg²⁺, Cu²⁺, and Ca²⁺ caused enhancement of enzyme activities whereas they were markedly inhibited by Zn²⁺, Hg²⁺, and Ag⁺. In vitro, B. thuringiensis and B. licheniformis chitinases had potential for cell wall lysis of many phytopathogenic fungi tested. The addition of B. thuringiensis chitinase was more effective than that of B. licheniformis in increasing the germination of soybean seeds infected with various phytopathogenic fungi.     

Characterization and constitutive expression of a novel endo-1,4-β-d-xylanohydrolase from Aspergillus niger in Pichia pastoris

A putative endo-1,4-β-d-xylanohydrolase gene xyl10 from Aspergillus niger, encoding a 308-residue mature xylanase belonging to glycosyl hydrolase family 10, was constitutively expressed in Pichia pastoris. The recombinant Xyl10 exhibited optimal activity at pH 5.0 and 60 °C with more than 50 % of the maximum activity from 40 to 70 °C. It retained more than 90 % of the original activity after incubation at 60 °C (pH 5.0) for 30 min and more than 74 % after incubation at pH 3.0–13.0 for 2 h (25 °C). The specific activity, K _m and V _max values for purified Xyl10 were, respectively, 3.2 × 10³ U mg^?1, 3.6 mg ml^?1 and 5.4 × 10³ μmol min^?1 mg^?1 towards beechwood xylan. The enzyme degraded xylan to a series of xylooligosaccharides and xylose. The recombinant enzyme with these properties has the potential for various industrial applications.     

The temperature-dependent self-association of beta-lactoglobulin C in glycine buffers

The self-association of β-lactoglobulin C at low pH (ca. 2.5) in glycine buffers has been studied at four temperatures, 10, 16, 20, and 25 °C, by low- and high-speed sedimentation equilibrium experiments. One buffer had an ionic strength of 0.1 and the other an ionic strength of 0.2. With either buffer the concentration dependence of the apparent weight average molecular weight, M_wa, was characteristic of a nonideal self-association. Like its genetic variants, β-lactoglobulin A and B, the self-association of β-lactoglobulin C increased with decreasing temperature; however, at the same temperature the association was always stronger in the buffer having the higher ionic strength. Several models were used to test the self-association, and a monomer-dimer self-association seemed to describe the self-association best with either buffer. Values of the association equilibrium constant, K₂, and the second virial coefficient, BM₁, are reported at each temperature for both series of experiments. Values of the thermodynamic functions, ΔG °, ΔH °, and ΔS °, are also reported for these experiments.     

The enthalpy of oxidation of flavin mononucleotide

The oxidation enthalpy of reduced flavin mononucleotide at pH 7.0 in 0.2 m phosphate buffer has been studied by determining the heat associated with the reaction: FMNH₂ + 2 Fe(CN)^?3₆ ? FMN + 2 Fe(CN)^?4₆ + 2 H⁺. (a) (The quinone, semiquinone, and hydroquinone forms of FMN are represented as FMN, FMNH, and FMNH₂, respectively.) Calorimetric experiments were performed in a flow microcalorimeter which was modified to prevent sample contamination by oxygen. The enthalpy observed for reaction (a), after correction for dilution and buffer effects, was ?39.2 ± 0.4 kcal (mole FMNH₂)^?1 at 25 °C. The potential difference, ΔE′, developed by reaction (a) was determined potentiometrically and corresponded to a free energy change, ΔG′, of ?30.3 kcal (mole FMNH₂)^?1. The resulting entropy change, ΔS′, was thus calculated to be ?29.8 e.u. Reaction (a) was also studied at temperatures of 7 °C and 35.5 °C. ΔC_p′ for the reaction was calculated as ?155 ± 18 cal deg^?1 (mole FMNH₂)^?1 at 20 °C. ΔH′ for the reaction (b), FMNH₂ ? FMN + H₂, (b) was calculated as +14.2 ± 0.7 kcal mole^?1 at 25 °C, relative to the enthalpy of the hydrogen electrode being identically equal to zero at all values of pH and temperature. The free energy at pH 7.0 for reaction (b), calculated from the potential was found to be ?9.7 kcal mole^?1, which resulted in an entropy for reaction (b) of 80.2 e.u. A thermal titration of reaction (a) was used to calculate the thermodynamic parameters for the formation of semiquinone dimer according to the reaction FMNH₂ + FMN ? (·FMNH)₂. (c) The free energy, enthalpy, and entropy changes for reaction (c) were estimated to be ?6.1 kcal mole^?1, ?7 kcal mole^?1, and ?3 e.u., respectively.     

Production and purification of a hyperthermostable chitinase from Brevibacillus formosus BISR-1 isolated from the Great Indian Desert soils

A strain of Brevibacillus formosus, capable of producing a high level of chitinase, was isolated and characterized for the first time from the Great Indian Desert soils. The production of extracellularly secreted chitinase was analyzed for its biocontrol potential and optimized by varying media pH, temperature, incubation period, substrate concentrations, carbon and nitrogen sources, etc. A twofold increase in chitinase production (798 IU/mL) was achieved in optimized media containing (g l^?1) chitin 2.0, malt extract 1.5, glycerol 1.0, ammonium nitrate 0.3 %, T-20 (0.1 %) and media pH 7.0 at 37 °C. The produced enzyme was purified using a three-step purification procedure involving ultra-filtration, ammonium sulphate precipitation and adsorption chromatography. The estimated molecular weight of the purified enzyme was 37.6 kDa. The enzyme was found thermostable at higher temperatures and showed a t _½ of more than 5 h at 100 °C. Our results show that the chitinase produced by B. formosus BISR-1 is thermostable at higher temperatures.