6LVW

Polyextremophilic Beta-galactosidase from the Antarctic haloarchaeon Halorubrum lacusprofundi

6LVW の概要

• エントリーDOI: 10.2210/pdb6lvw/pdb
• 分子名称: Beta-galactosidase Bga, ZINC ION, MAGNESIUM ION, ... (4 entities in total)
• 機能のキーワード: polyextremophilic enzyme, halophile, psychrophile, extremozyme, extremophile, sugar binding protein, hydrolase
• 由来する生物種: Halorubrum lacusprofundi (strain ATCC 49239 / DSM 5036 / JCM 8891 / ACAM 34)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 78226.09

構造登録者

Muhammad, R.,Arold, S.T. (登録日: 2020-02-06, 公開日: 2020-10-28, 最終更新日: 2023-11-29)

主引用文献

Karan, R.,Mathew, S.,Muhammad, R.,Bautista, D.B.,Vogler, M.,Eppinger, J.,Oliva, R.,Cavallo, L.,Arold, S.T.,Rueping, M.
Understanding High-Salt and Cold Adaptation of a Polyextremophilic Enzyme.
Microorganisms, 8:-, 2020

PubMed Abstract: The haloarchaeon is among the few polyextremophilic organisms capable of surviving in one of the most extreme aquatic environments on Earth, the Deep Lake of Antarctica (-18 °C to +11.5 °C and 21-28%, w/v salt content). Hence, has been proposed as a model for biotechnology and astrobiology to investigate potential life beyond Earth. To understand the mechanisms that allow proteins to adapt to both salinity and cold, we structurally (including X-ray crystallography and molecular dynamics simulations) and functionally characterized the β-galactosidase from (hla_bga). Recombinant hla_bga (produced in ) revealed exceptional stability, tolerating up to 4 M NaCl and up to 20% (v/v) of organic solvents. Despite being cold-adapted, hla_bga was also stable up to 60 °C. Structural analysis showed that hla_bga combined increased surface acidity (associated with halophily) with increased structural flexibility, fine-tuned on a residue level, for sustaining activity at low temperatures. The resulting blend enhanced structural flexibility at low temperatures but also limited protein movements at higher temperatures relative to mesophilic homologs. Collectively, these observations help in understanding the molecular basis of a dual psychrophilic and halophilic adaptation and suggest that such enzymes may be intrinsically stable and functional over an exceptionally large temperature range.

PubMed: 33081237
DOI: 10.3390/microorganisms8101594

実験手法

X-RAY DIFFRACTION (2.493 Å)