A new alkaline protease (AcpII) was purified from a culture of the deep-sea bacterium Alkalimonas collagenimarina AC40(T). AcpII degraded collagen three times faster than it degraded casein. The optimal pH was 8.5-9, and the optimal temperature was 45 degrees C for the degradation of collagen. AcpII was completely inhibited by phenylmethylsulfonyl fluoride and partially by EDTA. Cloning and sequencing the gene for AcpII revealed a 2,283-bp open reading frame encoding a protein of 760 amino acids. AcpII comprises a prepropeptide, a catalytic domain that includes a protease-associated domain (PA domain), and tandem repeat prepeptidase C-terminal domains. To elucidate the role of the PA domain of AcpII, we constructed genes for two enzyme derivatives that possessed the catalytic domains with or without the PA domain and expressed them in Escherichia coli. The derivative without the PA domain showed increased specific activities toward all proteinaceous substrates tested, including gelatin, casein, and collagen, compared with those of the derivative with the PA domain.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/s00253-009-2324-x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Microbial Communities in and Around the Siboglinid Tubeworms from the South Yungan East Ridge Cold Seep Offshore Southwestern Taiwan at the Northern South China Sea.
Microorganisms
November 2024
School of Resources and Chemical Engineering, Sanming University, Sanming 365004, China.
To date, only a few microbial community studies of cold seeps at the South China Sea (SCS) have been reported. The cold seep dominated by tubeworms was discovered at South Yungan East Ridge (SYER) offshore southwestern Taiwan by miniROV. The tubeworms were identified and proposed as sp.
View Article and Find Full Text PDFHeterologous Expression and Functional Verification of Extracellular Carbonic Anhydrases in from Mariana Trench.
Molecules
December 2024
Marine Natural Products Research and Development Key Laboratory of Qingdao, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China.
The exploration and exploitation of deep-sea microbial resources is of great scientific value for understanding biological evolution under extreme conditions. Deep-sea microorganisms are critical in the ocean carbon cycle, and marine heterotrophic microorganisms secrete extracellular carbonic anhydrase (CA) to fix inorganic carbon, an important process in climate regulation. Extracellular CA provides a green method for fixing carbon dioxide into stable minerals containing Ca.
View Article and Find Full Text PDFKey bacteria decomposing animal and plant detritus in deep sea revealed via long-term incubation in different oceanic areas.
ISME Commun
January 2024
Key Laboratory of Marine Genetic Resources, Ministry of Natural Resources of PR China, 178 Daxue Road, Siming District, Xiamen City, Fujian Province 361005, PR China.
Transport of organic matter (OM) occurs widely in the form of animal and plant detritus in global oceans, playing a crucial role in global carbon cycling. While wood- and whale-falls have been extensively studied, the process of OM remineralization by microorganisms remains poorly understood particularly in pelagic regions on a global scale. Here, enrichment experiments with animal tissue or plant detritus were carried out in three deep seas for 4-12 months using the deep-sea incubators.
View Article and Find Full Text PDFThermal sensitivity and niche plasticity of generalist and specialist leaf-endophytic bacteria in Mangrove Kandelia obovata.
Commun Biol
January 2025
Key Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Department of Oceanography, Key Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, China.
Leaf endospheres harbor diverse bacterial communities, comprising generalists and specialists, that profoundly affect ecosystem functions. However, the ecological dynamics of generalist and specialist leaf-endophytic bacteria and their responses to climate change remain poorly understood. We investigated the diversity and environmental responses of generalist and specialist bacteria within the leaf endosphere of mangroves across China.
View Article and Find Full Text PDFAntibacterial and Cytotoxic Methylthioether-Containing Cytochalasins from AS-506, an Endozoic Fungus Associated with Deep-Sea Sponge of Magellan Seamounts.
J Agric Food Chem
January 2025
CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Nanhai Road 7, Qingdao 266071, China.
Ten cytochalasin derivatives, including six new methylthioether-containing chaetoglobosins (thiochaetoglobosins A-F, ), a new related congener (18-nor-prochaetoglobosin II, ), and three known unsulfured counterparts (), were isolated and identified from AS-506, an endozoic fungus isolated from a deep-sea sponge, which was collected from Magellan Seamounts in the Western Pacific Ocean. Their structures were determined by extensive interpretation of the spectroscopic and X-ray crystallographic data, as well as by ECD calculations. Structurally, thiochaetoglobosins A-F () represent the first examples of chaetoglobosin derivatives containing a methylthioether group in the molecules, while 18-nor-prochaetoglobosin II () is the first 18-nor-chaetoglobosin derivative.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!