Cellulase production by pink pigmented facultative methylotrophic strains (PPFMs)

Area of Science:

• Microbiology
• Enzymology
• Biotechnology

Background:

• Pink pigmented facultative methylotrophs (PPFM) are widespread in various environments.
• Cellulase enzymes are crucial for biomass degradation and have industrial applications.
• Limited research exists on cellulase production by PPFM strains from Indian ecosystems.

Purpose of the Study:

• To screen PPFM from Tamil Nadu, India for extracellular cellulase production.
• To characterize the cellulase activity and properties of promising PPFM isolates.
• To identify and taxonomically classify PPFM strains exhibiting significant cellulolytic activity.

Main Methods:

• Isolation and screening of PPFM on carboxymethylcellulose agar (CMC agar) medium.
• Quantitative assays for cellulase activity (CMCase and filter paper assays).
• SDS-PAGE, zymogram analysis, scanning electron microscopy, and molecular identification (mxaF gene, 16S rRNA sequencing).

Main Results:

• Multiple PPFM strains exhibited varying degrees of cellulase production.
• Methylobacterium gregans, MNW 60, MHW 109, MSF 34, and MSF 40 showed notable cellulolytic activity (0.73–1.16 U mL⁻¹).
• Strain MNW 60 demonstrated broad temperature (35–65°C) and pH (5–8) tolerance, with identified cellulase bands at ~92 and 42 kDa.

Conclusions:

• The study reports the first detailed account of extracellular cellulase production by pink pigmented Methylobacterium sp. from India.
• Strain MNW 60, identified as Methylobacterium sp. with high similarity to Methylobacterium lusitanum, shows potential for industrial cellulase applications.
• Further research on strain improvement and large-scale production of cellulases from PPFMs is warranted.