Related Experiment Video
Updated: Jul 14, 2026
09:06
Removal of Exogenous Materials from the Outer Portion of Frozen Cores to Investigate the Ancient Biological Communities Harbored Inside
Published on: July 3, 2016
A cold-adapted esterase from psychrotrophic Pseudoalteromas sp. strain 643A.
Hubert Cieśliński1, Aneta M Białkowska, Anna Długołecka
1Departament of Microbiology, Gdańsk University of Technology, ul. Narutowicza 11/12, 80-952, Gdansk, Poland.
Archives of Microbiology
|May 23, 2007
Summary
A novel cold-adapted esterase was identified from Antarctic krill and characterized. This enzyme, EstA, shows optimal activity at moderate temperatures and stability at alkaline pH, offering potential biotechnological applications.
Area of Science:
- Microbiology
- Enzymology
- Biotechnology
Background:
- Psychrotrophic bacteria from extreme environments are sources of cold-adapted enzymes.
- Antarctic krill (Euphasia superba) inhabit cold marine ecosystems, potentially harboring unique microbial communities.
- Esterases are crucial enzymes with diverse industrial applications, particularly those active at low temperatures.
Purpose of the Study:
- To isolate and characterize a novel cold-adapted esterase from Antarctic krill.
- To determine the biochemical properties and potential applications of the identified esterase.
- To elucidate the genetic basis of the esterase production in a psychrotrophic bacterium.
Main Methods:
- Isolation and classification of a psychrotrophic bacterium (Pseudoalteromonas sp. strain 643A) from Antarctic krill.
- Cloning and sequencing of the esterase gene (estA) and analysis of the encoded protein (EstA).
- Purification and characterization of the native EstA esterase, including activity assays at various temperatures and pH levels, substrate specificity, and inhibition studies.
Main Results:
- A novel esterase gene (estA) was isolated from Pseudoalteromonas sp. strain 643A, encoding a 207-amino acid protein (EstA) belonging to the GDSL-lipolytic enzyme family.
- The purified EstA enzyme exhibited significant activity between 0-20°C, with optimal activity at 35°C, and was stable at alkaline pH (9-11.5).
- EstA displayed activity towards short- to medium-chain fatty acid esters and was inhibited by PMSF and reducing agents, with slight activation by Ca(2+).
Conclusions:
- Pseudoalteromonas sp. strain 643A produces a cold-adapted esterase (EstA) with unique biochemical properties.
- EstA's activity profile suggests potential applications in low-temperature industrial processes, such as food processing or detergent formulations.
- Further research into EstA could lead to the development of novel biocatalysts for biotechnological applications.
Related Concept Videos
01:27Factors Influencing Microbial Growth: Temperature
Microorganisms display remarkable adaptations, enabling them to thrive in diverse ecological niches across a wide range of temperatures. Temperature profoundly influences microbial growth by affecting enzymatic activity, membrane fluidity, and other cellular processes.Each microorganism operates within a specific temperature range defined by three cardinal points: minimum, optimum, and maximum. Below the minimum temperature, membranes lose fluidity, halting transport processes. Above the...
01:21Hyperthermophilic Bacteria
Domain Bacteria includes some unique hyperthermophilic species. They exhibit remarkable adaptations that enable survival in extreme environments.Thermotoga species are rod-shaped, gram-negative, non-sporulating hyperthermophiles that form a sheath-like envelope called a toga. They ferment sugars or starch, producing lactate, acetate, CO₂, and H₂, and can also grow via anaerobic respiration using H₂ and ferric iron. Found in hot springs and hydrothermal vents, over 20% of their genes show strong...
01:27Diversity of Archaea III
Crenarchaeota, a prominent phylum of Archaea, is remarkable for its ability to thrive in extreme environments characterized by high temperatures and acidity. These microorganisms inhabit sulfuric hot springs, volcanic systems, and submarine hydrothermal vents, where temperatures often exceed 100°C. The unique adaptations of Crenarchaeota not only allow survival under such extreme conditions but also provide insights into the mechanisms of life in primordial Earth-like environments.Morphological...
01:29Diversity of Archaea IV
Hyperthermophilic archaea are a group of extremophiles thriving at temperatures above 80°C, often in hydrothermal vents and volcanic soils where conditions surpass the boiling point of water. At such temperatures, proteins, membranes, and DNA in most organisms degrade, but hyperthermophiles have evolved remarkable adaptations to maintain stability and function.Unique Cellular FeaturesHyperthermophilic membranes are composed of a monolayer of biphytanyl tetraether lipids, which resist thermal...
01:18Deep Sea Microbial Ecology
The deep ocean and its underlying sediments represent vast, largely unexplored microbial habitats that extend far beyond the sunlit photic zone. The photic (euphotic) zone typically spans the upper ~100–200 meters of pelagic waters in the open ocean, but its depth varies geographically and seasonally, where sufficient light supports photosynthetic life. Below this lies the deep sea, spanning roughly 1000–6000 meters (bathypelagic to abyssal zones), with deeper hadal trenches extending beyond...
02:45Responses to Heat and Cold Stress
Every organism has an optimum temperature range within which healthy growth and physiological functioning can occur. At the ends of this range, there will be a minimum and maximum temperature that interrupt biological processes.