# A Novel Thermo-Alkaline Stable GDSL/SGNH Esterase with Broad Substrate Specificity from a Deep-Sea Pseudomonas sp

## TL;DR

A new esterase from a deep-sea Pseudomonas sp. shows stability in harsh conditions and could be useful for industrial applications.

## Contribution

Discovery of a novel thermo-alkaline stable esterase from a deep-sea Pseudomonas sp. with broad substrate specificity.

## Key findings

- EstGoM is a new esterase from a deep-sea Pseudomonas sp. with high activity at pH 9 and 60°C.
- EstGoM retains over 50% activity across pH 7–11 and temperatures 10–75°C, and is tolerant to high salt and detergents.
- EstGoM belongs to a new subgroup of lipolytic family II esterases and has broad substrate specificity.

## Abstract

Marine environments harbor a plethora of microorganisms that represent a valuable source of new biomolecules of biotechnological interest. In particular, enzymes from marine bacteria exhibit unique properties due to their high catalytic activity under various stressful and fluctuating conditions, such as temperature, pH, and salinity, fluctuations which are common during several industrial processes. In this study, we report a new esterase (EstGoM) from a marine Pseudomonas sp. isolated at a depth of 1000 m in the Gulf of Mexico. Bioinformatic analyses revealed that EstGoM is an autotransporter esterase (type Va) and belongs to the lipolytic family II, forming a new subgroup. The purified recombinant EstGoM, with a molecular mass of 67.4 kDa, showed the highest hydrolytic activity with p-nitrophenyl octanoate (p-NP C8), although it was also active against p-NP C4, C5, C10, and C12. The optimum pH and temperature for EstGoM were 9 and 60 °C, respectively, but it retained more than 50% of its activity over the pH range of 7–11 and temperature range of 10–75 °C. In addition, EstGoM was tolerant of up to 1 M NaCl and resistant to the presence of several metal ions, detergents, and chemical reagents, such as EDTA and β-mercaptoethanol. The enzymatic properties of EstGoM make it a potential candidate for several industrial applications.

The online version contains supplementary material available at 10.1007/s10126-024-10308-w.