scholarly journals Novel Glycerophospholipid, Lipo- and N-acyl Amino Acids from Bacteroidetes: Isolation, Structure Elucidation and Bioactivity

Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5195
Author(s):  
Mona-Katharina Bill ◽  
Stephan Brinkmann ◽  
Markus Oberpaul ◽  
Maria A. Patras ◽  
Benedikt Leis ◽  
...  
Keyword(s):  
Amino Acids ◽  
Structure Elucidation ◽  
High Resolution Mass Spectrometry ◽  
Inhibition Activity ◽  
Positive Bacterium ◽  
Gram Negative ◽  
The Core ◽  
Lipoamino Acids ◽  
Tyrosine 14 ◽  
Growth Inhibition Activity

The ‘core’ metabolome of the Bacteroidetes genus Chitinophaga was recently discovered to consist of only seven metabolites. A structural relationship in terms of shared lipid moieties among four of them was postulated. Here, structure elucidation and characterization via ultra-high resolution mass spectrometry (UHR-MS) and nuclear magnetic resonance (NMR) spectroscopy of those four lipids (two lipoamino acids (LAAs), two lysophosphatidylethanolamines (LPEs)), as well as several other undescribed LAAs and N-acyl amino acids (NAAAs), identified during isolation were carried out. The LAAs represent closely related analogs of the literature-known LAAs, such as the glycine-serine dipeptide lipids 430 (2) and 654. Most of the here characterized LAAs (1, 5–11) are members of a so far undescribed glycine-serine-ornithine tripeptide lipid family. Moreover, this study reports three novel NAAAs (N-(5-methyl)hexanoyl tyrosine (14) and N-(7-methyl)octanoyl tyrosine (15) or phenylalanine (16)) from Olivibacter sp. FHG000416, another Bacteroidetes strain initially selected as best in-house producer for isolation of lipid 430. Antimicrobial profiling revealed most isolated LAAs (1–3) and the two LPE ‘core’ metabolites (12, 13) active against the Gram-negative pathogen M. catarrhalis ATCC 25238 and the Gram-positive bacterium M. luteus DSM 20030. For LAA 1, additional growth inhibition activity against B. subtilis DSM 10 was observed.

Val-Geninthiocin: Structure Elucidation and MSn Fragmentation of Thiopeptide Antibiotics Produced by Streptomyces sp. RSF18

2008 ◽  
Vol 63 (10) ◽  
pp. 1223-1230 ◽  
Author(s):  
Imran Sajid ◽  
Khaled A. Shaaban ◽  
Holm Frauendorf ◽  
Shahida Hasnain ◽  
Hartmut Laatscha
Keyword(s):  
Amino Acids ◽  
Biological Activity ◽  
Antifungal Activity ◽  
Structure Elucidation ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Unusual Amino Acids ◽  
Streptomyces Sp ◽  
Gram Positive Bacteria ◽  
Thiopeptide Antibiotics

AbstractVal-Geninthiocin (2), a new member of thiopeptide antibiotics, was isolated from the mycelium of Streptomyces sp. RSF18, along with the closely related geninthiocin (1) and the macrolide, chalcomycin. By intensive NMR and MS studies, Val-geninthiocin (2) was identified as desoxygeninthiocin, a thiopeptide, containing several oxazole and thiazole units and a number of unusual amino acids. Compound 2 shows potent activity against Gram-positive bacteria and minor antifungal activity, while it is not effective against Gram-negative bacteria or microalgae. Here we describe the fermentation, isolation and structure elucidation as well as the biological activity of 2.

Haemophilus vaginalis 594, a Gram-negative organism?

1971 ◽  
Vol 17 (7) ◽  
pp. 865-869 ◽  
Author(s):  
B. Sue Criswell ◽  
Judith H. Marston ◽  
Wayne A. Stenback ◽  
S. H. Black ◽  
Herman L. Gardner
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Cell Wall ◽  
Bacillus Megaterium ◽  
Teichoic Acid ◽  
Biochemical Properties ◽  
Positive Bacterium ◽  
Gram Negative ◽  
Bacterium Bacillus ◽  
Escherichia Coli B

The fine structure of Haemophilus vaginalis 594 (ATCC 14018) was examined by electron microscopy, and the biochemical composition of its cell wall was determined. For comparison, similar studies were done with a Gram-positive bacterium, Bacillus megaterium KM, and a Gram-negative bacterium, Escherichia coli B. Both Haemophilus vaginalis 594 and Escherichia coli B possessed a multiple-layered cell wall containing 11 to 14 amino acids, a low mucopeptide content, and no teichoic acid. In contrast, Bacillus megaterium KM had a thick, amorphous cell wall with five amino acids, high mucopeptide content, and detectable amounts of teichoic acid. Haemophilus vaginalis 594 resembled Escherichia coli, a member of the Gram-negative group of organisms. The structural and biochemical properties of Haemophilus vaginalis, which are described in detail, may prove useful in determining the ultimate taxonomic position of this species.

scholarly journals Magnesium Supplementation Alters Leaf Metabolic Pathways for Higher Flavor Quality of Oolong Tea

Agriculture ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 120 ◽  
Author(s):  
Jiuliang Xu ◽  
Liangquan Wu ◽  
Bingxin Tong ◽  
Jiaxu Yin ◽  
Zican Huang ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Amino Acids ◽  
Free Amino Acids ◽  
Free Amino ◽  
High Resolution Mass Spectrometry ◽  
Southern China ◽  
Substantial Reduction ◽  
Sugar Accumulation ◽  
Limiting Factor ◽  
Oolong Tea

Oolong tea, one of the most famous tea beverages in China, contains specialized metabolites contributing to rich flavors and human health. Accumulation patterns of such metabolites and underlying regulatory mechanisms significantly vary under different growth conditions. To optimize quality and yield while minimizing environmental effects, three treatments were designed in this study: Conventional fertilization, optimized fertilization, and optimized fertilization supplemented with magnesium (Mg). We investigated the yield, taste quality, primary and secondary metabolites of oolong tea, and found that a substantial reduction in chemical fertilizers (nutrient optimization by reducing 43% N, 58% P2O5 and 55% K2O) did not affect the tea yield in this study. Interestingly, Mg fertilization is an important factor influencing amino acid and sugar accumulation in oolong tea, resulting in higher concentrations of total free amino acids and a lower ratio of tea polyphenols (TP) to free amino acids (FAA). Gas chromatography-time-of-flight mass spectrometry (GC-TOF-MS) and liquid chromatography-high resolution mass spectrometry (LC-HRMS) combined multivariate analyses revealed distinct features of metabolite accumulation in leaves of three different treatments, as indicated by 34 differentially accumulated characteristic compounds. The levels of serine, aspartic acid, isoleucine, phenylalanine, theanine, and proline were reduced by fertilizer optimization and increased by Mg supplementation. Mg particularly promoted theanine accumulation favoring a stronger umami taste of oolong tea, while decreasing astringency and bitter metabolites. Thus, Mg application paves a new path for tea quality improvement in Southern China where Mg deficiency in the soil is a frequent limiting factor for crop production.

scholarly journals Influence of spatial structure on protein damage susceptibility: a bioinformatics approach

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maximilian Fichtner ◽  
Stefan Schuster ◽  
Heiko Stark
Keyword(s):  
Amino Acids ◽  
Molecular Medicine ◽  
Protein Damage ◽  
Aging Research ◽  
Form And Function ◽  
The Core ◽  
And Function ◽  
Thermophilic Organisms ◽  
Damage Susceptibility ◽  
Protein Shell

AbstractAging research is a very popular field of research in which the deterioration or decline of various physiological features is studied. Here we consider the molecular level, which can also have effects on the macroscopic level. The proteinogenic amino acids differ in their susceptibilities to non-enzymatic modification. Some of these modifications can lead to protein damage and thus can affect the form and function of proteins. For this, it is important to know the distribution of amino acids between the protein shell/surface and the core. This was investigated in this study for all known structures of peptides and proteins available in the PDB. As a result, it is shown that the shell contains less susceptible amino acids than the core with the exception of thermophilic organisms. Furthermore, proteins could be classified according to their susceptibility. This can then be used in applications such as phylogeny, aging research, molecular medicine, and synthetic biology.

scholarly journals Long-distance electron transfer in a filamentous Gram-positive bacterium

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yonggang Yang ◽  
Zegao Wang ◽  
Cuifen Gan ◽  
Lasse Hyldgaard Klausen ◽  
Robin Bonné ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Microbial Fuel Cells ◽  
Extracellular Electron Transfer ◽  
Gram Negative Bacteria ◽  
Positive Bacterium ◽  
Long Distance ◽  
Gram Positive ◽  
Gram Negative ◽  
Force Microscopy ◽  
Cell Envelopes

AbstractLong-distance extracellular electron transfer has been observed in Gram-negative bacteria and plays roles in both natural and engineering processes. The electron transfer can be mediated by conductive protein appendages (in short unicellular bacteria such as Geobacter species) or by conductive cell envelopes (in filamentous multicellular cable bacteria). Here we show that Lysinibacillus varians GY32, a filamentous unicellular Gram-positive bacterium, is capable of bidirectional extracellular electron transfer. In microbial fuel cells, L. varians can form centimetre-range conductive cellular networks and, when grown on graphite electrodes, the cells can reach a remarkable length of 1.08 mm. Atomic force microscopy and microelectrode analyses suggest that the conductivity is linked to pili-like protein appendages. Our results show that long-distance electron transfer is not limited to Gram-negative bacteria.

scholarly journals Characterization of the 6'-N-aminoglycoside acetyltransferase gene aac(6')-Im [corrected] associated with a sulI-type integron.

1997 ◽  
Vol 41 (2) ◽  
pp. 314-318 ◽  
Author(s):  
E Hannecart-Pokorni ◽  
F Depuydt ◽  
L de wit ◽  
E van Bossuyt ◽  
J Content ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Amino Acid ◽  
Resistance Gene ◽  
Citrobacter Freundii ◽  
Gram Negative ◽  
Gene Environment ◽  
Insert Region ◽  
Klebsiella Spp

The amikacin resistance gene aac(6')-Im [corrected] from Citrobacter freundii Cf155 encoding an aminoglycoside 6'-N-acetyltransferase was characterized. The gene was identified as a coding sequence of 521 bp located down-stream from the 5' conserved segment of an integron. The sequence of this aac(6')-Im [corrected] gene corresponded to a protein of 173 amino acids which possessed 64.2% identity in a 165-amino-acid overlap with the aac(6')-Ia gene product (F.C. Tenover, D. Filpula, K.L. Phillips, and J. J. Plorde, J. Bacteriol. 170:471-473, 1988). By using PCR, the aac(6')-Im [corrected] gene could be detected in 8 of 86 gram-negative clinical isolates from two Belgian hospitals, including isolates of Citrobacter, Klebsiella spp., and Escherichia coli. PCR mapping of the aac(6')-Im [corrected] gene environment in these isolates indicated that the gene was located within a sulI-type integron; the insert region is 1,700 bases long and includes two genes cassettes, the second being ant (3")-Ib.

scholarly journals Deciphering the Enigma of the Histone H2A.Z-1/H2A.Z-2 Isoforms: Novel Insights and Remaining Questions

Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1167
Author(s):  
Manjinder S. Cheema ◽  
Katrina V. Good ◽  
Bohyun Kim ◽  
Heddy Soufari ◽  
Connor O’Sullivan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Amino Acids ◽  
Dna Damage ◽  
Chromosome Segregation ◽  
Multiple Roles ◽  
Histone H2a ◽  
The Core ◽  
Structural Differences ◽  
Functional Involvement ◽  
Insight Into

The replication independent (RI) histone H2A.Z is one of the more extensively studied variant members of the core histone H2A family, which consists of many replication dependent (RD) members. The protein has been shown to be indispensable for survival, and involved in multiple roles from DNA damage to chromosome segregation, replication, and transcription. However, its functional involvement in gene expression is controversial. Moreover, the variant in several groups of metazoan organisms consists of two main isoforms (H2A.Z-1 and H2A.Z-2) that differ in a few (3–6) amino acids. They comprise the main topic of this review, starting from the events that led to their identification, what is currently known about them, followed by further experimental, structural, and functional insight into their roles. Despite their structural differences, a direct correlation to their functional variability remains enigmatic. As all of this is being elucidated, it appears that a strong functional involvement of isoform variability may be connected to development.

Synthesis, structure elucidation, biological screening, molecular modeling and DNA binding of some Cu(II) chelates incorporating imines derived from amino acids

2016 ◽  
Vol 1103 ◽  
pp. 232-244 ◽  
Author(s):  
Laila H. Abdel-Rahman ◽  
Ahmed M. Abu-Dief ◽  
Mohammed Ismael ◽  
Mounir A.A. Mohamed ◽  
Nahla Ali Hashem
Keyword(s):  
Amino Acids ◽  
Molecular Modeling ◽  
Dna Binding ◽  
Structure Elucidation ◽  
Biological Screening

scholarly journals Clinical Trial on Solid 2nd Generation Platelet-Concentrates in the Management of the Chronic Osteomyelitis: An Advanced Regenerative Surgeries

2020 ◽  
Author(s):  
Alessandro Crisci ◽  
Raffaele D'Adamo ◽  
Michela Crisci
Keyword(s):  
Blood Count ◽  
Chronic Osteomyelitis ◽  
Therapeutic Option ◽  
Gram Negative Bacteria ◽  
Platelet Concentrates ◽  
Positive Bacterium ◽  
Cutaneous Lesions ◽  
Gram Negative ◽  
Cutaneous Injury ◽  
2Nd Generation

The supposition is that the usage of fibrin rich in leukocytes and platelets advanced (A-PRF) in ulcerative osteomyelitis of the diabetic foot allows rehabilitation from this critical illness. In this investigation, the focus was to normalize the use of PRF in patients with osteomyelitis not amputated, to use this second generation platelet concentrate as a regeneration enabler. The researchers submitted and utilized A-PRF membranes (1300 g × 8 min) in 7 patients (all diabetics) with osteomyelitis and cutaneous injury for 6 months. The membranes, in combination with the supernatant fluid produced by stress, have been integrated into the skin lesion down to the bone after surgical debridement. The advancement of the lesions after some period of time has been analyzed. All seven subjects had a Probe-to-Bone positive assay; MRI indicated a cortico-periosteal coagulation and/or foci of cortico-spongeous osteolysis contiguous to the lesion. Gram-positive bacterium were identified in our procedures in 52% of cases. Gram+ Cocci, for example, S. Aureus (15.6%), S. Hemolytic (12.1%), S. Viridans (7.1%), and Gram-negative Bacteria, for example, Pseudomonas (10.6%), Proteus (7.8%), Enterobacter (5.7%) are present. Candida Albicans is active in 2.8%. The blood count shows no relevant differences. To date, cutaneous lesions have cured in 6 of the seven subjects treated (one patient for more than five years) without any evidence of infection or recurrence. The results obtained on our subjects indicate that PRF membranes may be a therapeutic option in this problematic disease.

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