海洋细菌中铁载体的分离纯化和活性研究

从海洋来源的细菌发酵液中分离得到三个铁载体,其中化合物3为新化合物,化合物1和2为已知化合物nocardamine和schizokinen A。 通过CAS液体检测的方法测定了三个化合物的最低活性浓度,分别为：5, 4 及156μg/mL。     

Alginate Lyases from Marine Bacteria: An Enzyme Ocean for Sustainable Future

The cell wall of brown algae contains alginate as a major constituent. This anionic polymer is a composite of β-d-mannuronate (M) and α-l-guluronate (G). Alginate can be degraded into oligosaccharides; both the polymer and its products exhibit antioxidative, antimicrobial, and immunomodulatory activities and, hence, find many commercial applications. Alginate is attacked by various enzymes, collectively termed alginate lyases, that degrade glycosidic bonds through β-elimination. Considering the abundance of brown algae in marine ecosystems, alginate is an important source of nutrients for marine organisms, and therefore, alginate lyases play a significant role in marine carbon recycling. Various marine microorganisms, particularly those that thrive in association with brown algae, have been reported as producers of alginate lyases. Conceivably, the marine-derived alginate lyases demonstrate salt tolerance, and many are activated in the presence of salts and, therefore, find applications in the food industry. Therefore, this review summarizes the structural and biochemical features of marine bacterial alginate lyases along with their applications. This comprehensive information can aid in the expansion of future prospects of alginate lyases.     

Isolation and Characterization of Levan from Moderate Halophilic Bacteria Bacillus licheniformis BK AG21

Levan is fructose polymer as the result of biosynthesis by levansucrase. This study is aimed to explore the potential of moderate halophilic bacteria Bacillus licheniformis BK AG21 isolated from Bledug Kuwu, Purwodadi Central Java, in producing levan. This bacteria displayed positive potential in producing levan based on the appearance of slime mucoid on a sucrose medium. The optimum production of levan was attained when the culture medium containing sucrose and peptone as respective carbon and nitrogen sources was shaking incubated with speed of 150 rpm for 24 hours at 37 ^oC. Thermal gravimetric analysis revealed that levan produced by B. licheniformis BK AG21 decomposed at 214 ^oC. The structure of the isolated levan was elucidated with FTIR, ¹H and ¹³C NMR spectroscopies. Based on the obtained spectroscopic data, the isolated levan was composed of β-(2,6)-linkages of fructose residues.     

Isolation,Molecular Identification and Amino Acid Profiling of Single-Cell-Protein-Producing Phototrophic Bacteria Isolated from Oil-Contaminated Soil Samples

In the current study, soil samples were gathered from different places where petrol and diesel filling stations were located for isolation of photosynthetic bacteria under anaerobic conditions using the paraffin wax-overlay pour plate method with Biebl and Pfennig’s medium. The three isolated strains were named Rhodopseudomonas palustris SMR 001 (Mallapur), Rhodopseudomonas palustris NR MPPR (Nacahram) and Rhodopseudomonas faecalis N Raju MPPR (Karolbagh). The morphologies of the bacteria were examined with a scanning electron microscope (SEM). The phylogenetic relationship between R. palustris strains was examined by means of 16S rRNA gene sequence analysis using NCBI-BLAST search and a phylogenetic tree. The sequenced data for R. palustris were deposited with the National Centre for Biotechnology Research (NCBI). The total amino acids produced by the isolated bacteria were determined by HPLC. A total of 14 amino acids and their derivatives were produced by the R. palustris SMR 001 strain. Among these, carnosine was found in the highest concentration (8553.2 ng/mL), followed by isoleucine (1818.044 ng/mL) and anserine (109.5 ng/mL), while R. palustris NR MPPR was found to produce 12 amino acids. Thirteen amino acids and their derivatives were found to be produced from R. faecalis N Raju MPPR, for which the concentration of carnosine (21601.056 ng/mL) was found to be the highest, followed by isoleucine (2032.6 ng/mL) and anserine (227.4 ng/mL). These microbes can be explored for the scaling up of the process, along with biohydrogen and single cell protein production.     

海洋细菌对柠檬烯的生物转化及萜类产物鉴定

从南海大亚湾的海洋微生物中筛选出3株对单萜D-柠檬烯有显著生物催化转化作用的海洋细菌(Vibrio cholerae、Listonella dam sela和Vibrio alginolyticus)。以2216E为培养基,添加200mg/L的柠檬烯,在28℃,以120 r/m in摇瓶培养5 d,用乙酸乙酯提取培养液,经GC-MS分析其转化产物,结果显示,这些细菌能在柠檬烯的不同位置进行羟基化、羰基化等,并伴随有还原、水解、酯化、开环等反应,但转化能力和转化程度不同;在产物中,还检测到系列结构不同的其它萜类:包括倍半萜、二萜以及三萜等,这些萜类化合物的产生跟柠檬烯的加入有关,说明柠檬烯能影响细菌代谢产物的产生。单萜微生物转化反应操作简单、条件温和、高效率和高选择性、无毒、环境友好,能够分离发现系列新的在医药、有机合成、精细化工等领域有用的化合物,为丰富的天然单萜资源的开发与利用提供新的途径和方法。     

Isolation and Characterization of Bacteria that Degrade Poly (Lactic Acid-Glycerol Ester)-Type Time-Release Electron Donors for Accelerated Biological Reductive Dechlorination

Hydrogen Release Compound (HRC^TM) is an important electron donor that has recently become available and is now becoming widely applied to the accelerated biological reductive dechlorination of chloroethenes such as tetrachloroethene (PCE) and trichloroethene (TCE). HRC is a benign poly(lactic acid-glycerol ester) specially formulated for the slow time-release of lactic acid. Lactic acid is then metabolized to hydrogen, which can be used in the reductive dechlorination of chloroethenes. To establish an advance diagnosis of the HRC addition effect for the bioremediation of polluted sites, 17 strains of HRC-degrading bacteria were isolated by liquid- and plate-culture methods. All these strains could grow on a basal medium containing purified HRC as the sole carbon source. The sequence analysis of the 16S rDNAs of 6 of the 17 strains shows that they all belong to the family β-Proteobacteria, which includes Burkholderia cepacia, Burkholderia vietnamiensis, Ralstonia sp., and Variovorax paradoxus. The time course of HRC degradaton by strains JM-11, JM-12 and JM-13 showed that the HRC degradation rates after 9 days of cultivation were 81.1%, 82.8% and 80.4%, respectively. Preliminary assay of the activities of the HRC-degrading enzyme indicated that HRC degradation may be specifically performed by specific lipases produced by HRC-degrading microorganisms.     

Synthesis and Pharmacological Studies on a Cyclooligopeptide from Marine Bacteria

A natural proline‐rich tetrapeptide cyclo‐prolyl‐leucyl‐prolyl‐phenylalanyl was prepared employing solution‐phase method of peptide synthesis through coupling of dipeptide fragments Boc‐l‐Pro‐l‐Leu‐OH and l‐Pro‐l‐Phe‐OMe which utilizes diisopropylcarbodiimide (DIPC) as coupling agent and N‐methylmorpholine (NMM) as the base. Deprotection of linear tetrapeptide unit followed by its cyclization provided a cyclopeptide, identical in all aspects to the natural molecule. Pharmacological evaluation showed cytotoxic, antifungal and antihelmintic potential of synthesized peptide against Dalton's Lymphoma Ascites (DLA) and Ehrlich's Ascites Carcinoma (EAC) cell lines, pathogenic dermatophytes and earthworms.     

Chemical Diversity and Biological Activity of Secondary Metabolites Isolated from Indonesian Marine Invertebrates

Marine invertebrates have been reported to be an excellent resource of many novel bioactive compounds. Studies reported that Indonesia has remarkable yet underexplored marine natural products, with a high chemical diversity and a broad spectrum of biological activities. This review discusses recent updates on the exploration of marine natural products from Indonesian marine invertebrates (i.e., sponges, tunicates, and soft corals) throughout 2007–2020. This paper summarizes the structural diversity and biological function of the bioactive compounds isolated from Indonesian marine invertebrates as antimicrobial, antifungal, anticancer, and antiviral, while also presenting the opportunity for further investigation of novel compounds derived from Indonesian marine invertebrates.     

Degradation of PCB by Bacteria Isolated from Long-Time Contaminated Soil

Abstract

Four bacterial isolates belonging to the genera Pseudomonas and Alcaligenes were obtained by the enrichment method, using biphenyl as the sole carbon source, from the soil, which underwent long-time contamination with technical mixtures of PCB. Kinetics of PCB degradation by individual isolates was measured using n-hexane extraction of the cultivation media in proper time intervals and analysed by congener specific gas chromatography with electron capture detection. All isolates exhibit interesting biodegradative potential. Specific degradation of individual congeners with respect to the number and position of chlorine substituents is discussed. The influence of glucose, biphenyl and 3-chlorobenzoic acid on the PCB degradation has been assessed.     

Bioreduction of Acetophenone Derivatives by Red Marine Algae Bostrychia radicans and B. tenella,and Marine Bacteria Associated

The biocatalytic reduction of acetophenone derivatives was exploited by using algal biomass from Bostrychia radicans and B. tenella producing exclusively (S)‐2‐phenylethanols with high enantiomeric excess (>99% ee). Bacterial populations associated with algal biomass were identified as the Bacillus genus. This report deals with the first investigations involving the use of marine bacteria associated with B. radicans and B. tenella marine algae for the biocatalytic reduction of acetophenone derivatives.     

Microbial Electricity Generation and Isolation of Exoelectrogenic Bacteria Based on Petroleum Hydrocarbon‐contaminated Soil

In this study, the petroleum hydrocarbon‐contaminated soil was used as both inoculation and carbon source simultaneously to enrich exoelectrogenic bacteria for using in microbial fuel cell system and it demonstrated working output power density at around 220 mW m^?2. The feasible electrochemical properties have displayed by means of cyclic voltammetry and dual‐chamber MFCs experiments. Moreover, two species of exoelectrogens were isolated belonging to Geobacter sp. and Ochrobactrum sp., respectively. This work evaluates the capability of naturally occurring petroleum‐degrading species to produce electric current in bioelectrochemical system. To the best of our knowledge, this is the first time when ecological information on electroactive, petroleum‐degrading consortium is provided.     

Isolation and Characterization of Antibacterial Conglutinins from Lupine Seeds

The main target of this work is to discover new protein fractions from natural resources with high antibacterial action. The 7S and 11S globulin fractions, as well as the basic subunit (BS), were isolated from lupine seeds (Lupinus termis), chemically characterized, and screened for antibacterial activity against seven pathogenic bacteria. SDS-PAGE revealed molecular weights ranging from 55 to 75 kDa for 7S globulin, 20–37 kD for 11S globulin, and 20 kD for the BS. 11S globulin and the BS migrated faster on Urea-PAGE toward the cathode compared to 7S globulin. FTIR and NMR showed different spectral patterns between the 7S and 11S globulins but similar ones between 11S globulin and the BS. The MICs of the BS were in the range of 0.05–2 μg/mL against Listeria monocytogenes, Klebsiella oxytoca, Proteus mirabilis, Staphylococcus aureus, Listeria ivanovii, Salmonella typhimurium, and Pseudomonas aeruginosa compared to higher values for 11S globulin. The BS surpassed 11S globulin in antibacterial action, while 7S globulin showed no effect. The MICs of 11S globulin and the BS represented only 5% and 2.5% of the specific antibiotic against L. monocytogenes, respectively. Scanning electron microscopy (SEM) demonstrated different signs of cellular deformation and decay in the protein-treated bacteria, probably due to interaction with the bacterial cell wall and membranes. 11S globulin and the BS can be nominated as effective food biopreservatives.     

Isolation and Characterization of Actinoramides A-C, Highly Modified Peptides from a Marine Streptomyces sp

Reported herein is the isolation and structure elucidation of three highly modified peptides, actinoramides A-C (1-3), which are produced by a marine bacterium closely related to the genus Streptomyces. The planar structures of the actinoramides, which are composed of the unusual amino acids 2-amino-4-ureidobutanoic acid and 4-amino-3-hydroxy-2-methyl-5-phenylpentanoic acid, were assigned by chemical transformations and by interpretation of spectroscopic data, while the absolute configuration of these new peptides were defined by application of the advanced Marfey’s and Mosher’s methods.     

Isolation and Partial Characterization of Halotolerant Lactic Acid Bacteria from Two Mexican Cheeses

Isolated strains of halotolerant or halophilic lactic acid bacteria (HALAB) from Cotija and doble crema cheeses were identified and partially characterized by phenotypic and genotypic methods, and their technological abilities were studied in order to test their potential use as dairy starter components. Humidity, a_w, pH, and salt concentration of cheeses were determined. Genotypic diversity was evaluated by randomly amplified polymorphic DNA-polymerase chain reaction. Molecular identification and phylogenetic reconstructions based on 16S rRNA gene sequences were performed. Additional technological abilities such as salt tolerance, acidifying, and proteolytic and lipolytic activities were also investigated. The differences among strains reflected the biodiversity of HALAB in both types of cheeses. Lactobacillus acidipiscis, Tetragenococcus halophilus, Weissella thailandensis, and Lactobacillus pentosus from Cotija cheese, and L. acidipiscis, Enterococcus faecium, Lactobacillus plantarum, Lactobacillus farciminis, and Lactobacillus rhamnosus from doble crema cheese were identified based on 16S rRNA. Quantitative and qualitative assessments showed strains of T. halophilus and L. plantarum to be proteolytic, along with E. faecium, L. farciminis, and L. pentosus to a lesser extent. Lipolytic activity could be demonstrated in strains of E. faecium, L. pentosus, L. plantarum, and T. halophilus. Strains belonging to the species L. pentosus, L. plantarum, and E. faecium were able to acidify the milk media. This study evidences the presence of HALAB that may play a role in the ripening of cheeses.     

Isolation and Characterization of PHA-Producing Bacteria from Propylene Oxide Saponification Wastewater Residual Sludge

Single-chain variable fragment (scFv) antibodies as therapeutic agents have the potential to reduce the production cost and immunogenicity relative to monoclonal antibodies, but their monovalency and lack of a fragment crystallizable region can lead to reduced function. Multimerization is one strategy for recovering the function; however, their application is limited by the production of multimeric proteins. In our previous study, an anti-lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) scFv showed potential use in diagnosis and therapy of atherosclerotic diseases, but is limited by its inherent low antigen-binding activity. In this study, to improve the efficacy of the anti-LOX-1 scFv, we constructed the anti-LOX-1 scFv multimers by modifying the linker length between the variable domains of the scFv or by fusing the scFv with self-merization domains and expressed these scFv multimers in Brevibacillus choshinensis hosts. After optimization, all of the scFv multimers obtained efficient secretion expression. Compared with the scFv monomer, the multimers that are successfully fractionated displayed increased neutralization activity and showed elevated antigen-binding avidity, especially the tetramer, which improved the antigen avidity by two orders of magnitude. Moreover, the scFv dimer and the tetramer both displayed better stability and longer half-life in serum, which can be attractive candidates for the next-generation anti-LOX-1 therapeutic antibody.     

Isolation of bacterial culture capable of degrading triphenyltin pesticides

A bacterial culture capable of degrading triphenyltin hydroxide (TPTOH) was successfully isolated from soil samples taken at a dockyard area in Samutprakarn province, Thailand. It was purified, identified and designated as Pseudomonas putida no. C. The bacterium isolated was found to have the capability of degrading TPTOH at levels of 7.0 ppm in 24 h. The addition of glucose enhanced the extent of degradation of TPTOH. Experiments were also conducted to immobilize P. putida no. C on various supports such as sand, cotton fibre and alginate. It was found that alginate was the best support material. Immobilized P. putida no. C on alginate was found to possess suitable characteristics and potential for future development in the removal of TPTOH from water and waste water systems.     

Genotypic Diversity of Mosquitocidal Bacteria (Bacillus sphaericus, B. thuringiensis, and B. cereus) Newly Isolated from Natural Sources

In the present study, to comprehend the genetic diversity of mosquitocidal bacteria, the genotypic analysis of 30 strains of Bacillus species isolated newly from diverse environmental sources has been conducted. Randomly amplified polymorphic DNA polymerase chain reaction was conducted to characterize the genotype diversity between the bacterial strains. The matrix of scores from each bacterial DNA was analyzed, and the correlation between the co-efficients and the similarity matrix data was computed. Clusters from dendrogram showing diversity among isolates could be distinguished genetically based on their origin of isolates. The first major cluster consists of 43 strains grouped under various subclusters (91.489 %). A second cluster contains only four strains (8.511 %). An average similarity value of 0.36 revealed the dendrogram split into 28 distinct “groups” or “clusters,” allowing almost a complete separation of strains within the Bacillus group isolated from various sources and thus facilitating assessment of genetic diversity of species and subspecies level. The conclusion from the result was that there was broad diversity among the mosquitocidal strains, and cluster analysis revealed the associations among the isolates based on their origin. A high level of polymorphism with distinct genetic lineages consequent to the source of origin of bacterial strains is the significant impact of this study.     

Natural Products Produced in Culture by Biosynthetically Talented Salinispora arenicola Strains Isolated from Northeastern and South Pacific Marine Sediments

Laboratory cultures of two ‘biosynthetically talented’ bacterial strains harvested from tropical and temperate Pacific Ocean sediment habitats were examined for the production of new natural products. Cultures of the tropical Salinispora arenicola strain RJA3005, harvested from a PNG marine sediment, produced salinorcinol (3) and salinacetamide (4), which had previously been reported as products of engineered and mutated strains of Amycolatopsis mediterranei, but had not been found before as natural products. An S. arenicola strain RJA4486, harvested from marine sediment collected in the temperate ocean waters off British Columbia, produced the new aminoquinone polyketide salinisporamine (5). Natural products 3, 4, and 5 are putative shunt products of the widely distributed rifamycin biosynthetic pathway.     

Effects of Ulva sp. Extracts on the Growth,Biofilm Production,and Virulence of Skin Bacteria Microbiota: Staphylococcus aureus,Staphylococcus epidermidis,and Cutibacterium acnes Strains

Ulva sp. is known to be a source of bioactive compounds such as ulvans, but to date, their biological activity on skin commensal and/or opportunistic pathogen bacteria has not been reported. In this study, the effects of poly- and oligosaccharide fractions produced by enzyme-assisted extraction and depolymerization were investigated, for the first time in vitro, on cutaneous bacteria: Staphylococcus aureus, Staphylococcus epidermidis, and Cutibacterium acnes. At 1000 μg/mL, poly- and oligosaccharide fractions did not affect the growth of the bacteria regarding their generation time. Polysaccharide Ulva sp. fractions at 1000 μg/mL did not alter the bacterial biofilm formation, while oligosaccharide fractions modified S. epidermidis and C. acnes biofilm structures. None of the fractions at 1000 μg/mL significantly modified the cytotoxic potential of S. epidermidis and S. aureus towards keratinocytes. However, poly- and oligosaccharide fractions at 1000 μg/mL induced a decrease in the inflammatory potential of both acneic and non-acneic C. acnes strains on keratinocytes of up to 39.8%; the strongest and most significant effect occurred when the bacteria were grown in the presence of polysaccharide fractions. Our research shows that poly- and oligosaccharide Ulva sp. fractions present notable biological activities on cutaneous bacteria, especially towards C. acnes acneic and non-acneic strains, which supports their potential use for dermo-cosmetic applications.     

In Vitro and In Vivo Characterization of Plant Growth Promoting Bacillus Strains Isolated from Extreme Environments of Eastern Algeria

This report is to our knowledge the first to study plant growth promotion and biocontrol characteristics of Bacillus isolates from extreme environments of Eastern Algeria. Seven isolates of 14 (50 %) were screened for their ability to inhibit growth of some phytopathogenic fungi on PDA and some roots exudates. The bacteria identification based on 16S r-RNA and gyrase-A gene sequence analysis showed that 71 % of the screened isolates belonged to Bacillus amyloliquefaciens and the rest were closely related to B. atrophaeus and B. mojavensis. Most of them had high spore yields (22?×?10⁸–27?×?10⁸ spores/ml). They produced protease and cellulase cell wall-degrading enzymes while the chitinase activity was only observed in the B. atrophaeus (6SEL). A wide variety of lipopeptides homologous was detected by liquid chromatography–electrospray ionization–mass spectrometry analysis. Interestingly, some additional peaks with new masses were characterized, which may correspond to new fengycin classes. The isolates produced siderophores and indole-3- acetic acid phytohormone. The greenhouse experiment using a naturally infested soil with Sclerotonia sclerotiorum showed that the B. atrophaeus (6SEL) significantly increased the size of the chickpea plants and reduced the stem rot disease (P?<?0.05). These results suggest that these isolates may be used further as bio-inoculants to improve crop systems.