Optimization of Nutrients and Culture Conditions for Alkaline Protease Production Using Two Endophytic Micrococci: Micrococcus aloeverae and Micrococcus yunnanensis

Molecular dynamics and simulation analysis against superoxide dismutase (SOD) target of Micrococcus luteus with secondary metabolites from Bacillus licheniformis recognized by genome mining approach

Micrococcus luteus, also known as M. luteus, is a bacterium that inhabits mucous membranes, human skin, and various environmental sources. It is commonly linked to infections, especially among individuals who have compromised immune systems. M. luteus is capable of synthesizing the enzyme superoxide dismutase (SOD) as a component of its protective response to reactive oxygen species (ROS). This enzyme serves as a promising target for drug development in various diseases. The current study utilized a subtractive genomics approach to identify potential therapeutic targets from M. luteus. Additionally, genome mining was employed to identify and characterize the biosynthetic gene clusters (BGCs) responsible for the production of secondary metabolites in Bacillus licheniformis (B. licheniformis), a bacterium known for its production of therapeutically relevant secondary metabolites. Subtractive genomics resulted in identification of important extracellular protein SOD as a drug target that plays a crucial role in shielding cells from damage caused by ROS. Genome mining resulted in identification of five potential ligands (secondary metabolites) from B. licheniformis such as, Bacillibactin (BAC), Paenibactin (PAE), Fengycin (FEN), Surfactin (SUR) and Lichenysin (LIC). Molecular docking was used to predict and analyze the binding interactions between these five ligands and target protein SOD. The resulting protein-ligand complexes were further analyzed for their motions and interactions of atoms and molecules over 250 ns using molecular dynamics (MD) simulation analysis. The analysis of MD simulations suggests, Bacillibactin as the probable candidate to arrest the activities of SOD. All the five compounds reported in this study were found to act by directly/indirectly interacting with ROS molecules, such as superoxide radicals (O2-) and hydrogen peroxide (H2O2), and transforming them into less reactive species. This antioxidant activity contributes to its protective effects against oxidative stress-induced damage in cells making them likely candidate for various applications, including in the development of antioxidant-based therapies, nutraceuticals, and functional foods.

First case report of human infection with Micrococcus yunnanensis identified by 16S rRNA gene sequencing: A case report

BACKGROUND

Micrococcus yunnanensis (M. yunnanensis) is an endophytic actinomycete that was originally isolated from the roots of Polyspora axillaris in 2009, and no human infections caused by this organism have yet been reported. We report the first case of community-acquired pneumonia caused by M. yunnanensis and propose that M. yunnanensis should be considered as an emerging pathogen in medical practice. A 30-year-old woman was admitted to our hospital with fever, paroxysmal dry cough with sputum, and pharyngalgia. Laboratory tests revealed an increase in several inflammatory indicators, and a computerized tomography scan of the chest showed scattered infection foci in both lungs. Bronchoalveolar lavage fluid was collected via bronchoscopy for microbial culture and pathological examination.

METHODS

The isolate from bronchoalveolar lavage fluid was identified as M. yunnanensis by 16S rRNA gene sequencing. The patient was diagnosed with community-acquired pneumonia based on the diagnostic criteria.

RESULTS

The patient was treated with intravenous amoxicillin/clavulanate potassium, levofloxacin hydrochloride tablets, and compound methoxyphenamine capsules on the day after admission. After 3 days of treatment, the patient's physiological conditions and inflammatory indicators normalized, and 6-month follow-up showed no abnormalities.

CONCLUSION

Although the pathogenicity of M. yunnanensis is unclear, the present case indicates an emerging pathogen in medical practice. MALDI-TOF MS has a limited ability to identify novel or rare pathogenic species, and 16S rRNA gene sequencing is of great value in some circumstance.

Understanding the Basis of Occurrence, Biosynthesis, and Implications of Thermostable Alkaline Proteases

The group of hydrolytic enzymes synonymously known as proteases is predominantly most favored for the class of industrial enzymes. The present work focuses on the thermostable nature of these proteolytic enzymes that occur naturally among mesophilic and thermophilic microbes. The broad thermo-active feature (40-80 °C), ease of cultivation, maintenance, and bulk production are the key features associated with these enzymes. Detailing of contemporary production technologies, and controllable operational parameters including the purification strategies, are the key features that justify their industrial dominance as biocatalysts. In addition, the rigorous research inputs by protein engineering and enzyme immobilization studies add up to the thermo-catalytic features and application capabilities of these enzymes. The work summarizes key features of microbial proteases that make them numero-uno for laundry, biomaterials, waste management, food and feed, tannery, and medical as well as pharmaceutical industries. The quest for novel and/or designed and engineered thermostable protease from unexplored sources is highly stimulating and will address the ever-increasing industrial demands.

Aptitude of endophytic microbes for production of novel biocontrol agents and industrial enzymes towards agro-industrial sustainability

Background

Endophytes have continued to receive increased attention worldwide, probably, due to the enormous biotechnological potentials spanning through various industrial sectors. This paper outlines the biotechnological potentials of endophytes in biocontrol and industrial enzyme production, and the possible contribution towards achieving agro-industrial sustainability using published articles on endophytes in both Web of Science and Scopus (1990–2020).

Main body of the abstract

This review discusses the potential of endophytes to produce novel secondary metabolites with effective biocontrol activity against insect pests and plant pathogens. More so, the aptitude of endophytes for production of a wide range of enzymes with potential applications in agriculture, energy and health is discussed in this review. Furthermore, this review highlights the emerging potentials of endophytes in the production of exopolysaccharide and fatty acids. This paper also advocates the need for bioprospecting endophytes for novel biocontrol agents against termites, which are known for causing significant damage to forest and stored products.

Short conclusion

Exploration of endophytes for biocontrol and production of biomolecules of industrial significance could contribute significantly towards agricultural and industrial sustainability.