GLYCOCONJUGATE JOURNAL
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2022
·Vol. 39
·期 6
·773-787
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IF 3.009
Li Fengshu,Hu Xin,Sun Xiaojun,Li Haoshuai,Lu Jinren,Li Yiming,Bao Mutai
The pH value was essential for the growth and metabolism of microorganisms. Acidic pH exopolysaccharide (AC-EPS) and alkaline pH exopolysaccharide (AL-EPS) secreted by A. australica QD mediated by pH were studied in this paper. The total carbohydrate content and molecular weight of AC-EPS (79.59% ± 2.24% (w/w), 8.374 × 10 5 Da) and AL-EPS (82.48% ± 1.46% (w/w), 6.182 × 10 5 Da) were estimated and compared. In AC-EPS, mannose (3.78%) and galactose (3.24%) content was more, while the proportion of glucuronic acid was less in comparison to AL-EPS. The scanning electron microscopy revealed the structural differences among the AC-EPS and AL-EPS. Thermogravimetric analysis showed degradation temperatures of 272.8 °C and 244.9 °C for AC-EPS and AL-EPS, respectively. AC-EPS was found to exhibit better rheological properties and emulsifying capabilities, while AL-EPS had superior antioxidant activities. Overall, both AC-EPS and AL-EPS have the potential to be used as emulsifiers and biological antioxidants.
Graphical Abstract
研究领域:
微生物学
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食品科学
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生物化学
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DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
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2024
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IF 9.7
Dingxi Zhang,Bowei Chu,Qingqing Yang,Xiaoyan Zhang,Yingying Fang,Guangliang Liu,Lina Liang,Yingying Guo,Yongguang Yin,Yong Cai,Guibin Jiang
Mercury (Hg), particularly organic mercury, poses a global concern due to its pronounced toxicity and bioaccumulation. Bioremediation of organic mercury in high-salt wastewater faces challenges due to the growth limitations imposed by elevated Cl − and Na + concentrations on microorganisms. In this study, an isolated marine bacterium Alteromonas macleodii KD01 was demonstrated to degrade methylmercury (MeHg) efficiently in seawater and then was applied to degrade organic mercury (MeHg, ethylmercury, and thimerosal) in simulated high-salt wastewater. Results showed that A. macleodii KD01 can rapidly degrade organic mercury (within 20 min) even at high concentrations (>10 ng/mL), volatilizing a portion of Hg from the wastewater. Further analysis revealed an increased transcription of organomercury lyase ( merB ) with rising organic mercury concentrations during the exposure process, suggesting the involvement of mer operon ( merA and merB ). These findings highlight A. macleodii KD01 as a promising candidate for addressing organic mercury pollution in high-salt wastewater.
研究领域:
环境微生物学
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生物修复
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海洋生物学
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毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED PHYCOLOGY
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2023
·
IF 3.3
Tang Tiancheng,Li Chen,Zhu Benwei,Yao Zhong
Ulvan lyase is a useful tool which can degrade ulvan into oligosaccharides with a range of biological activities. In this study, the ulvan lyase ULA-3 from Alteromonas sp. 76–1, which was a 1467-bp encoded 489-amino acid residue protein, has been cloned, heterologously expressed and biochemically characterized. ULA-3 showed the maximum activity at 45 ˚C and pH 9.0. The K m is 1.879 mg mL −1 and V max is 2.597 µmol min −1 mL −1 . Its enzyme activity was outstanding at 11.754 U mg −1 . Moreover, its metal ion stability is exceptionally good and most metal ions at a concentration of 1 mM have no inhibitory effect on its activity. It can endolytically degrade ulvan into oligosaccharides with a degree of polymerization (Dp) of 2–4 and with unsaturated double bond through the β -elimination reaction, which mainly cleaves the glycosidic bond between rhamnose and uronic acids. All in all, our study has increased the ulvan lyase database and offers the opportunity to fully utilize ulvan, a green biomass resource from marine algae.
研究领域:
生物化学
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生物技术
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海洋生物学
✓ 已验证
产品关联
DOI
高影响因子
Algal Research-Biomass Biofuels and Bioproducts
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2022
·
IF 5.276
Tiancheng Tang,Benwei Zhu,Zhong Yao
Ulvan , extracted from the marine green algae belonging to the genus Ulva , is a complex water-soluble sulfated polysaccharide which mainly composed of four monosaccharides consisting of rhamnose , xylose , glucuronic acid and iduronic acid . Its complex monosaccharide composition gives ulvan great potential for application in the fields of food, pharmaceuticals, and chemistry. And it can be degraded by ulvan lyases mainly from Polysaccharide Lyases (PL) family of PL24, PL25 and PL28 through β -elimination mechanism, which cleaves the β -glycosidic bond between sulfated rhamnose and glucuronic acid or iduronic acid, thereby producing an Ulva oligosaccharide with unsaturated bond. In this study, we have identified a putative ulvan lyase from Alteromonas sp. TK-45 (2). We heterologously expressed, purified, and biochemically characterized the ulvan lyase, which has removed signal peptide . The results show that ULA-1 had best activity at 45 °C and pH 8.0. The K m and V max values were 13.25 μg·mL −1 and 1.719 μmol·min −1 ·mL −1 , respectively. The thermostability of ULA-1 was excellent, and its activity hardly decreased after incubation at 45 °C for 1 h. ESI-MS analysis showed that the primary end-product were disaccharides to tetrasaccharides . In conclusion, our research has expanded the database of ulvan lyase, and provided the possibility to make full use of ulvan, a huge marine biomass resource .
研究领域:
海洋生物学
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酶学
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生物技术
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生物化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
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2025
·
IF 4.3
Songzhi Li,Yang Guo,Hong Jiang,Huan Zhang,Jiayu Li,Yanli Chen,Jie Li,Xiangzhao Mao,Minxiao Wang
Arylsulfatase catalyzes the cleavage of sulfate ester bonds and plays a role in agar desulfation, thereby enhancing agar gel strength and quality. While studying the desulfurization pathway in Pseudoalteromonassp. SR43-6, a sequence encoding a potential arylsulfatase─Pseudoalteromonas Ars (Ps-Ars)─was found. The enzyme, with p-nitrophenyl sulfate as a substrate, exhibited optimal activity at 35 °C and pH 8.0. Its relative activity (206 U/mg) exceeded that of the recently identified arylsulfatases. Four hundred units of the enzyme removed 86.4% of sulfate groups from Gelidium amansii agar in 4 h, whereas 800 U of the enzyme removed 71.3% of sulfate groups from Gracilaria lemaneiformis agar in 8 h. After enzymatic treatment, G. amansii agar gel strength was enhanced by 32%, and a similar improvement was observed in G. lemaneiformis agar gel strength. Enzymatic agar desulfurization offers mild, quality-retaining, and environmentally friendly advantages, augmenting industrial application prospects.
研究领域:
生物化学
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海洋微生物学
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食品科学
✓ 已验证
DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2021
·
IF 7.514
Chenlu Zhu,Zebin Liu,Lishi Ren,Siming Jiao,Xuebing Zhang,Qiukuan Wang,Zhimin Li,Yuguang Du,Jian-Jun Li
Endo -fucoidanases are important in structural analysis of fucoidans and preparation of fuco-oligosaccharides. However their enzymological properties and analysis of degradation products are scarcely investigated. Truncated endo - α (1 → 3)-fucoidanase Fda1 (tFda1B from Alteromonas sp. was overexpressed and characterized, showing highest activity at pH 7.0, 35 °C, and 1.0 M NaCl. Its K m and k cat were 3.88 ± 0.81 mg/mL and 0.82 ± 0.17 min −1 . Fe 3+ and Mn 2+ enhanced activity by 100% and 19.5% respectively. Co 2+ and Cu 2+ completely inactivated tFda1B, whereas Ni 2+ , Mg 2+ , Zn 2+ , Pb 2+ , Ca 2+ , Ba 2+ and Li + decreased activity by 58.8%, 56.0%, 50.6%, 47.7%, 28.9%, 15.6% and 37.5%, respectively. Catalytic residues were identified through structure and sequence alignment, and confirmed by mutagenesis. Degradation products of Kjellmaniella crassifolia fucoidan by tFda1B were characterized by LC-ESI-MS/MS, confirming tFda1B belongs to endo -(1 → 3)-fucoidanases, and backbone of K. crassifolia fucoidan is 1 → 3 fucoside linkage. This endo - α (1 → 3)-fucoidanase would be useful for elucidating fucoidan structures, and be used as a food enzyme.
研究领域:
生物化学
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酶学
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海洋生物技术
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分析化学
✓ 已验证
DOI
PubMed
高影响因子
GLYCOBIOLOGY
·
2023
·
IF 4.3
Li Chen,Tang Tiancheng,Jiang Jinju,Yao Zhong,Zhu Benwei
Ulva is globally distributed specie and has a high economic value. Ulvan is one of the main active substances in Ulva, which has a variety of biological properties. Ulvan lyase degrades ulvan through a β-elimination mechanism which cleaves the β-glycosidic bond between Rha3S and GlcA or IdoA. The complex monosaccharide composition of ulvan makes it promising for use in food and pharmaceutical applications. This thesis explores a putative ulvan lyase from Alteromonas sp. KUL_42. We expressed and purified the protein, performed a series of characterizations and signal peptide had been removed. The results showed that the protein molecular weight of ULA-2 was 53.97 kDa, and it had the highest catalytic activity at 45 °C and pH 8.0 in Tris–HCl buffer. The Km and Vmax values were 2.24 mg·mL−1 and 2.048 μmol·min−1·mL−1, respectively. The activity of ULA-2 was able to maintain more than 80% at 20 ~ 30 °C. ESI-MS analysis showed that the primary end-products were mainly disaccharides to tetrasaccharides. The study of ULA-2 enriches the ulvan lyase library, promotes the development and high-value utilization of Ulva resources, and facilitates further research applications of ulvan lyase in ulva oligosaccharides.
研究领域:
生物化学
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生物技术
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海洋生物学
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食品科学
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药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Marine Life Science & Technology
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2025
·
IF 5.3
Wang Yan,Wang Zhen,Zhao Wen-Xiao,Yuan Xiao-Jie,Yu Yang,Wang Peng,Wang Min,McMinn Andrew,Zhang Yu-Zhong,Peng Ming,Fu Hui-Hui,Chen Xiu-Lan
Free trans -4-hydroxy-L-proline (T4LHyp), a non-proteinogenic amino acid, is mainly released from the degradation of collagen, hydroxyproline-rich glycoproteins, and some peptide antibiotics in nature. Although it has been known that some terrestrial bacteria utilize T4LHyp as carbon and nitrogen source via a T4LHyp gene cluster, which and how marine microorganisms catabolize T4LHyp still remains unclear. Here, five T4LHyp-utilizing marine bacterial strains, Halomonas sp. 5021, Salinicola sp. 4072, Alteromonas sp. 6022, Alteromonas sp. 5112 and Alteromonas sp. 30521, were isolated from hydrothermal vent sediment samples collected from the southwest Indian Ocean. While Halomonas sp. 5021 can utilize T4LHyp as both a nitrogen and carbon source, the other four strains can utilize T4LHyp as only a nitrogen source. Then, the T4LHyp catabolic mechanisms of Halomonas sp. 5021 and Salinicola sp. 4072, as a representative of the four strains, were further investigated by genomic, transcriptional, and biochemical analyses. Halomonas sp. 5021 adopts an intact T4LHyp gene cluster containing four enzymes to catabolize T4LHyp into NH 3 and α-ketoglutarate to provide nitrogen and carbon sources for its growth. Compared to Halomonas sp. 5021, Salinicola sp. 4072 lacks an α-KGSA dehydrogenase gene in the T4LHyp gene cluster and can only catabolize T4LHyp into NH 3 and α-ketoglutarate semialdehyde to provide a nitrogen source for its growth. Bioinformatic investigation showed that the 5021-like and 4072-like T4LHyp gene clusters are predominantly found in bacteria from Pseudomonadota , which are widely distributed in multiple marine habitats. Thus, Pseudomonadota bacteria are likely the dominant group to drive the recycling and mineralization of T4LHyp in the ocean.
研究领域:
海洋微生物学
·
微生物生态学
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生物化学
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基因组学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）