Thermostable chitinase from Cohnella sp. A01: isolation and product optimization

Abstract

Twelve bacterial strains isolated from shrimp farming ponds were screened for their growth activity on chitin as the sole carbon source. The highly chitinolytic bacterial strain was detected by qualitative cup plate assay and tentatively identified to be Cohnella sp. A01 based on 16S rDNA sequencing and by matching the key morphological, physiological, and biochemical characteristics. The cultivation of Cohnella sp. A01 in the suitable liquid medium resulted in the production of high levels of enzyme. The colloidal chitin, peptone, and K2HPO4 represented the best carbon, nitrogen, and phosphorus sources, respectively. Enzyme production by Cohnella sp. A01 was optimized by the Taguchi method. Our results demonstrated that inoculation amount and temperature of incubation were the most significant factors influencing chitinase production. From the tested values, the best pH/temperature was obtained at pH 5 and 70 °C, with Km and Vmax values of chitinase to be 5.6 mg/mL and 0.87 μmol/min, respectively. Ag+, Co2+, iodoacetamide, and iodoacetic acid inhibited the enzyme activity, whereas Mn2+, Cu2+, Tweens (20 and 80), Triton X-100, and EDTA increased the same. In addition, the study of the morphological alteration of chitin treated by enzyme by SEM revealed cracks and pores on the chitin surface, indicating a potential application of this enzyme in several industries.

Agrowastes as Feedstock for the Production of Endo-β-Xylanase from <b><i>Cohnella</i></b> sp. Strain AR92

“…A similar outcome was reported for extracellular chitinase production by Cohnella sp. A01 [Aliabadi et al, 2016]. In our study, a final endoxylanase titer of 46.3 ± 1.0 IU/mL was achieved, implying an overall 9-fold improvement, with respect to the screening medium containing birchwood xylan as a carbon source (5.0 ± 0.3 IU/mL for 96 h).…”

“…Among the few current reports, an intracellular GH10 xylanase from C. laeviribosi HY-21 was cloned and characterized by means of site-directed mutagenesis ; a thermophilic lipase from Cohnella sp. A01 was also cloned and characterized after purification of the recombinant product [Golaki et al, 2015]; and the production of chitinase from the A01 strain was recently published [Aliabadi et al, 2016].…”

Process Optimization on Chitinase Production by Locally Isolated Enterobacter sp. and Zymomonas sp.

“…growth well under slight acidic condition that was at pH 6 with the chitinase production of 5.08 ± 0.17 U/mL. Some microorganisms are able to produce high amount of chitinase under alkaline condition [3], [5], [20], while some microorganism preferable acidic condition for chitinase production [22], [24]. This can conclude that pH plays an important role production of chitinase.…”

A Cold-Adapted Chitinase-Producing Bacterium from Antarctica and Its Potential in Biocontrol of Plant Pathogenic Fungi

“…ANU 6277 [18], Lysinibacillus fusiformis B-CM18 [19], Streptomyces griseorubens C9 [20], Streptomyces pratensis KLSL55 [21], Humicola grisea ITCC 10360.16 [22], Cohnella sp. A01 [23], Serratia marcescens JPP1 [24] and Stenotrophomonas maltophilia [25], their chitinolytic activities are still fairly low, especially at low and intermediate temperatures, which leads to the high cost and limited large-scale application of chitinases or chitinase-producing microorganisms. As a rule of thumb, cold-adapted enzymes usually display higher activity than their mesophilic and thermophilic counterparts at the same temperature [26].…”