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1.
Ecol Evol ; 14(7): e11589, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38979007

ABSTRACT

Beetles have a remote evolutionary history dating back to the Carboniferous, with Mesozoic fossils playing a pivotal role in elucidating the early evolution of extant families. Despite their exceptional preservation in amber, deciphering the systematic positions of Mesozoic trogossitid-like beetles remains challenging. Here, we describe and illustrate a new trogossitid-like lineage from mid-Cretaceous Kachin amber, Foveapeltis rutai Li, Kolibác, Liu & Cai, gen. et sp. nov. Foveapeltis stands out within the Cleroidea due to the presence of a significant large cavity on each hypomeron. While the exact phylogenetic placement of Foveapeltis remains uncertain, we offer a discussion on its potential affinity based on our constrained phylogenetic analyses.

2.
Parasitol Res ; 123(7): 264, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38980469

ABSTRACT

Ticks are ectoparasite vectors of pathogens affecting human and animal health worldwide. Rational integration of different control interventions including plant-derived repellents and acaricides, management of natural predators, and vaccines is required for innovative approaches to reduce the risks associated with ticks and tick-borne diseases. How tick populations are naturally controlled is always a question. Tick interactions with other arthropods including predators evolved from ancient times. In this study, Cretaceous (ca. 100 Mya) Burmese amber inclusions were identified as probably related to Compluriscutula vetulum (Acari: Ixodida: Ixodidae) tick larvae and spider silk. As illustrated in this study, ancient interactions between ticks and spiders may support arthropod predatory behavior as a natural control intervention. Rational integrative management of different tick control interventions including natural predators under a One Health perspective will contribute to effectively and sustainably reducing the risks associated with ticks and tick-borne diseases.


Subject(s)
Predatory Behavior , Spiders , Animals , Spiders/physiology , Ixodidae/physiology , Larva/physiology
3.
IUCrJ ; 11(Pt 4): 643-644, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38958017

ABSTRACT

The manuscript `Modeling a unit cell: crystallographic refinement procedure using the biomolecular MD simulation platform Amber' presents a novel protein structure refinement method claimed to offer improvements over traditional techniques like Refmac5 and Phenix. Our re-evaluation suggests that while the new method provides improvements, traditional methods achieve comparable results with less computational effort.


Subject(s)
Molecular Dynamics Simulation , Proteins , Proteins/chemistry , Crystallography, X-Ray , Protein Conformation , Macromolecular Substances/chemistry , Software , Models, Molecular
4.
PeerJ ; 12: e17515, 2024.
Article in English | MEDLINE | ID: mdl-38948233

ABSTRACT

Burmese amber preserves a diverse assemblage of Cretaceous arachnids, and among pseudoscorpions (Arachnida: Pseudoscorpiones), ten species in five families have already been named. Here, we describe a new fossil species from Burmese amber in the pseudoscorpion family Hyidae, providing detailed measurements, photographs and 3D-models from synchrotron scanning. Based on morphology, the new fossil, Hya fynni sp. nov. is placed in the genus Hya, and is nearly identical to extant species in the genus, except for the position of trichobothrium est on the pedipalpal chela, thereby indicating extreme morphological stasis in this invertebrate lineage over the last 99 million years. Hya fynni represents the first described fossil species in Hyidae, and the third described Burmese fossil in the superfamily Neobisioidea. It also joins the garypinid, Amblyolpium burmiticum, in representing the oldest fossil records for extant pseudoscorpion genera. Considering proposed divergence dates, the newly described fossil species bolsters a Gondwanan origin for Hyidae, and provides evidence for the "Late Jurassic Rifting" hypothesis for the Burma Terrane, in which this landmass rifted from Gondwana in the Late Jurassic and collided with Eurasia by the Cretaceous/Eocene. Like Hya species today, H. fynni likely inhabited humicolous microhabitats in tropical forests on the Burma Terrane, supporting ecological niche stasis for this family since the Mesozoic.


Subject(s)
Amber , Arachnida , Fossils , Animals , Arachnida/classification , Arachnida/anatomy & histology , Biological Evolution , Myanmar , Phylogeny
5.
Int J Paediatr Dent ; 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-39031911

ABSTRACT

BACKGROUND: There is limited evidence of succinic acid release from amber necklace that justifies its biological plausibility. AIM: This study aimed to evaluate the release of succinic acid from Baltic amber beads in the presence of Staphylococcus epidermidis. DESIGN: The Baltic amber beads from the necklace were stratified according to their weight (average 0.05 g ± 0.067). Subsequently, the beads (n = 8) were submerged in 0.9% buffered saline (Control) or brain-heart infusion culture medium in the presence of a commercial strain of S. epidermidis, a resident skin bacterium incubated at 37°C for 24 h or 7 days. The samples were centrifuged, and the supernatants were analyzed by 1H Nuclear Magnetic Resonance. Multivariate analyses were adopted using the sparse partial least squares discriminant analysis method (p < .05). RESULTS: The group incubated with saline solution showed small release of succinic acid only after 7 days. In the groups with S. epidermidis, the release of succinic acid was observed in the both presence and absence of amber beads, indicating that succinic acid is a product released by bacteria. CONCLUSIONS: It was found that amber beads do not exhibit the ability to release expressive succinic acid, especially in a short period of time, which does not justify their use in infants. The most production of succinic acid is tributed to S. epidermidis.

6.
Ecol Evol ; 14(6): e11487, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38932960

ABSTRACT

A new species of the extant staphylinid genus Vicelva Moore & Legner, V. rasilis sp. nov., is reported from mid-Cretaceous Kachin amber of northern Myanmar. Vicelva rasilis is distinguishable from extant members of Vicelva by the smoother dorsal surface of head, pronotum and elytra, less prominent median projection of clypeus, unnotched mesal edge of mandibles, semiglabrous antennomere 6, and longer tarsomere 1. The pollen-containing coprolite attached to the beetle and the crystals within the beetle body provide valuable information about the biology and taphonomy of the fossil.

7.
Insects ; 15(6)2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38921157

ABSTRACT

The abundance of insects in Burmese amber illustrates a highly diverse insect community from the mid-Cretaceous period; yet, records of crickets (Grylloidea) are notably scarce. In this study, we describe two new genera with three new species, Palaeotrigonidium concavoculus gen. et sp. nov., Palaeotrigonidium defectivus sp. nov., and Tricalcaratus longilineus gen. et sp. nov., based on three specimens collected in north Myanmar. These new species can be placed within the Trigonidiidae (Orthoptera: Grylloidea) by their triangular head, compound eyes that protrude in dorsal view, and a body entirely covered with robust setae, particularly noticeable in the head and pronotum; however, subfamily assignments are not possible. Another known species, Birmaninemobius hirsutus, Xu et al., 2020, from Myanmar amber is redescribed based on a new specimen and a recheck of the holotype.

8.
J Biomol Struct Dyn ; : 1-8, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38910432

ABSTRACT

Myelin Oligodendrocyte Glycoprotein (MOG) is a transmembrane protein in the myelin sheath. It acts as an auto-antigen under certain unknown conditions causing demyelination, thus resulting in Myelin Oligodendrocyte Glycoprotein Antibody-associated Disease (MOGAD). The significance of glycosylation in the conformational dynamics of the extracellular region (EC1) of the MOG were evident from the previous computational studies. Here, in this study, we performed the molecular dynamics simulation of the entire human MOG in the myelin sheath for 100 ns using the NAMD program. The results indicated that the EC1 and cytoplasmic region (CP) dominate the conformational rigidity of the protein, and enhance its interaction with lipids. This in turn helps in maintaining the myelin integrity in the presence of glycan. The transmembrane regions have reduced interaction with lipids in the glycosylated system. Moreover, the C-terminal extracellular region 2 (EC2) behaves exactly opposite to that of EC1 in the glycan presence. This may be attributed to the glycosylation site in the EC1 region. Hence, not only the region EC1 (having 3 crucial epitopes) but even the CP region were important for understanding the proper function of MOG in the glycan presence.Communicated by Ramaswamy H. Sarma.

9.
Int J Mol Sci ; 25(12)2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38928405

ABSTRACT

Intrinsically disordered proteins (IDPs) pose challenges to conventional experimental techniques due to their large-scale conformational fluctuations and transient structural elements. This work presents computational methods for studying IDPs at various resolutions using the Amber and Gromacs packages with both all-atom (Amber ff19SB with the OPC water model) and coarse-grained (Martini 3 and SIRAH) approaches. The effectiveness of these methodologies is demonstrated by examining the monomeric form of amyloid-ß (Aß42), an IDP, with and without disulfide bonds at different resolutions. Our results clearly show that the addition of a disulfide bond decreases the ß-content of Aß42; however, it increases the tendency of the monomeric Aß42 to form fibril-like conformations, explaining the various aggregation rates observed in experiments. Moreover, analysis of the monomeric Aß42 compactness, secondary structure content, and comparison between calculated and experimental chemical shifts demonstrates that all three methods provide a reasonable choice to study IDPs; however, coarse-grained approaches may lack some atomistic details, such as secondary structure recognition, due to the simplifications used. In general, this study not only explains the role of disulfide bonds in Aß42 but also provides a step-by-step protocol for setting up, conducting, and analyzing molecular dynamics (MD) simulations, which is adaptable for studying other biomacromolecules, including folded and disordered proteins and peptides.


Subject(s)
Amyloid beta-Peptides , Disulfides , Intrinsically Disordered Proteins , Molecular Dynamics Simulation , Amyloid beta-Peptides/chemistry , Amyloid beta-Peptides/metabolism , Disulfides/chemistry , Intrinsically Disordered Proteins/chemistry , Humans , Protein Structure, Secondary , Peptide Fragments/chemistry , Protein Conformation
10.
Protein Sci ; 33(7): e5038, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38864725

ABSTRACT

Peptidoglycan is a major constituent of the bacterial cell wall. Its integrity as a polymeric edifice is critical for bacterial survival and, as such, it is a preeminent target for antibiotics. The peptidoglycan is a dynamic crosslinked polymer that undergoes constant biosynthesis and turnover. The soluble lytic transglycosylase (Slt) of Pseudomonas aeruginosa is a periplasmic enzyme involved in this dynamic turnover. Using amber-codon-suppression methodology in live bacteria, we incorporated a fluorescent chromophore into the structure of Slt. Fluorescent microscopy shows that Slt populates the length of the periplasmic space and concentrates at the sites of septation in daughter cells. This concentration persists after separation of the cells. Amber-codon-suppression methodology was also used to incorporate a photoaffinity amino acid for the capture of partner proteins. Mass-spectrometry-based proteomics identified 12 partners for Slt in vivo. These proteomics experiments were complemented with in vitro pulldown analyses. Twenty additional partners were identified. We cloned the genes and purified to homogeneity 22 identified partners. Biophysical characterization confirmed all as bona fide Slt binders. The identities of the protein partners of Slt span disparate periplasmic protein families, inclusive of several proteins known to be present in the divisome. Notable periplasmic partners (KD < 0.5 µM) include PBPs (PBP1a, KD = 0.07 µM; PBP5 = 0.4 µM); other lytic transglycosylases (SltB2, KD = 0.09 µM; RlpA, KD = 0.4 µM); a type VI secretion system effector (Tse5, KD = 0.3 µM); and a regulatory protease for alginate biosynthesis (AlgO, KD < 0.4 µM). In light of the functional breadth of its interactome, Slt is conceptualized as a hub protein within the periplasm.


Subject(s)
Bacterial Proteins , Pseudomonas aeruginosa , Pseudomonas aeruginosa/enzymology , Pseudomonas aeruginosa/metabolism , Pseudomonas aeruginosa/genetics , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/chemistry , Periplasm/metabolism , Periplasm/enzymology , Periplasmic Proteins/metabolism , Periplasmic Proteins/genetics , Periplasmic Proteins/chemistry , Glycosyltransferases/metabolism , Glycosyltransferases/genetics , Glycosyltransferases/chemistry , Peptidoglycan/metabolism , Peptidoglycan/chemistry
11.
AMB Express ; 14(1): 60, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38782816

ABSTRACT

Genetic code expansion involves introducing non-canonical amino acids (ncAAs) with unique functional groups into proteins to broaden their applications. Orthogonal aminoacyl tRNA synthetase (aaRS), essential for genetic code expansion, facilitates the charging of ncAAs to tRNA. In this study, we developed a new aaRS mutant from Methanosaeta concilii tyrosyl-tRNA synthetase (Mc TyrRS) to incorporate para-azido-L-phenylalanine (AzF). The development involved initial site-specific mutations in Mc TyrRS, followed by random mutagenesis. The new aaRS mutant with amber suppression was isolated through fluorescence-activated cell sorting. The M. concilii aaRS mutant structure was further analyzed to interpret the effect of mutations. This research provides a novel orthogonal aaRS evolution pipeline for highly efficient ncAA incorporation that will contribute to developing novel aaRS from various organisms.

12.
Transfus Med ; 34(3): 227-230, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38741419

ABSTRACT

INTRODUCTION: Abnormal colour of plasma is infrequently identified during processing of blood and blood components. Common reasons include haemolysis, medications or diet related. Sometimes, the aetiology is unknown. It is a dilemma for every transfusion specialist encountering this situation. Effort should be made to find the aetiology of discolouration of plasma, so that the blood donor can be suitably advised, and a decision can be made regarding the use of blood products. MATERIALS AND METHODS: We encountered two cases of orange coloured (amber coloured) plasma in our regular blood donors. All the common reasons for abnormal plasma discolouration were evaluated, including the donor's medication and diet. Spectrophotometry along with Liquid Chromatography-Mass Spectrometry (LC-MS) in both the positive and negative ion modes with literature search helped in arriving at a conclusion. RESULTS: Haemolysis was ruled out by estimation of plasma haemoglobin. Spectrophotometric analysis of the coloured plasma samples showed a peak, which was absent in normal coloured plasma. This was further investigated using Liquid Chromatography-Mass Spectrometry (LC-MS) in both the positive and negative ion modes. There was no significant difference between the coloured and normal samples in the positive ion mode. But in the negative ion mode, there was a peak observed at 110.5 and 191 m/z value in the profile of the coloured samples in comparison with the normal sample. Literature review shows the peak was corresponding to the presence of quinic acid residues-a substance found in coffee, and potentially excreted into the plasma of an individual with high coffee consumption. CONCLUSION: Reporting unusual causes associated with plasma discolouration is important. Present guidelines forbid issue of abnormal coloured blood and blood components for transfusion. Further such reports are necessary to confirm the safety of recipients receiving such units. This is the first case report to our knowledge of quinic acid discolouring blood products.


Subject(s)
Plasma , Humans , Male , Female , Plasma/chemistry , Blood Donors , Adult , Color , Mass Spectrometry , Hemolysis , Chromatography, Liquid
13.
Insects ; 15(5)2024 May 13.
Article in English | MEDLINE | ID: mdl-38786907

ABSTRACT

A new praeaulacid genus and species, Azygdellitha nova gen. et sp. nov., is described and illustrated based on a male specimen from mid-Cretaceous Kachin amber from Hukawng Valley, Myanmar. This newly discovered taxon increased the diversity of praeaulacid wasps during the Cretaceous period. While this new taxon shares similarities of wing venation with most species of the subfamily Praeaulacinae, it strongly differs from that of three genera previously described from mid-Cretaceous Kachin amber: Mesevania, Paleosyncrasis, and Praegastrinus. We explore the possibility that these genera constitute a distinct tribe within the Praeaulacinae, distinguished by their wing venation. We provide illustrations and emphasize the potentially diagnostic traits supporting this classification.

14.
Data Brief ; 54: 110478, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38770042

ABSTRACT

The article presents experimental data on vibrational spectroscopy of worldwide amber and amber-like resins. IR spectra were obtained using SHIMADZU IRPrestige-2 (Japan). Raman spectra were obtained using a Virsa Raman analyzer (UK). The data includes analyzed IR and Raman spectra of amber and amber-like resins, obtained to identify markers that determine spectral characteristics of natural resin and its deposits.

15.
Pharmaceuticals (Basel) ; 17(5)2024 May 03.
Article in English | MEDLINE | ID: mdl-38794156

ABSTRACT

Traditionally, amber (Succinite) has been used to alleviate all types of pain, skin allergies, and headaches. However, no studies have been conducted on its antidiabetic and antioxidant effects. In this study, differentiated skeletal muscle C2C12 cells were used to demonstrate the protective effects of amber (AMB) against H2O2-induced cell death. In addition, the effects of AMB on glucose uptake and ATP production were investigated. Our results showed that AMB at 10, 25, and 50 µg/mL suppressed the elevation of ROS production induced by H2O2 in a dose-dependent manner. Moreover, AMB enhanced glucose utilization in C2C12 cells through the improvement of ATP production and an increase in PGC-1α gene expression resulting in an amelioration of mitochondrial activity. On the other hand, AMB significantly increased the gene expression of glucose transporters GLUT4 and GLUT1. Our finding suggests that AMB can be used as a natural supplement for diabetes treatment and for the promotion of skeletal muscle function.

16.
J Biol Inorg Chem ; 29(2): 243-250, 2024 03.
Article in English | MEDLINE | ID: mdl-38580821

ABSTRACT

Calmodulin (CaM) binds to a linker between the oxygenase and reductase domains of nitric oxide synthase (NOS) to regulate the functional conformational dynamics. Specific residues on the interdomain interface guide the domain-domain docking to facilitate the electron transfer in NOS. Notably, the docking interface between CaM and the heme-containing oxygenase domain of NOS is isoform specific, which is only beginning to be investigated. Toward advancing understanding of the distinct CaM-NOS docking interactions by infrared spectroscopy, we introduced a cyano-group as frequency-resolved vibrational probe into CaM individually and when associated with full-length and a bi-domain oxygenase/FMN construct of the inducible NOS isoform (iNOS). Site-specific, selective labeling with p-cyano-L-phenylalanine (CNF) by amber suppression of CaM bound to the iNOS has been accomplished by protein coexpression due to the instability of recombinant iNOS protein alone. We introduced CNF at residue 108, which is at the putative CaM-heme (NOS) docking interface. CNF was also introduced at residue 29, which is distant from the docking interface. FT IR data show that the 108 site is sensitive to CaM-NOS complex formation, while insensitivity to its association with the iNOS protein or peptide was observed for the 29 site. Moreover, narrowing of the IR bands at residue 108 suggests the C≡N probe experiences a more limited distribution of environments, indicating side chain restriction apparent for the complex with iNOS. This initial work sets the stage for residue-specific characterizations of structural dynamics of the docked states of NOS proteins.


Subject(s)
Calmodulin , Spectrophotometry, Infrared , Calmodulin/chemistry , Calmodulin/metabolism , Nitric Oxide Synthase Type II/chemistry , Nitric Oxide Synthase Type II/metabolism , Protein Binding , Molecular Docking Simulation
17.
Insects ; 15(4)2024 Apr 13.
Article in English | MEDLINE | ID: mdl-38667400

ABSTRACT

Diptera are one of the four megadiverse groups of holometabolan insects. Flies perform numerous ecological functions, especially in their larval stages. We can assume that this was already the case in the past; however, fly larvae remain rare in most deposits. Here we report new dipteran larvae preserved in Cretaceous (about 99 Ma) Kachin amber from Myanmar and, even older, Jurassic (about 165 Ma) compression fossils from China. Through light microscopy and micro-CT scanning we explore their peculiar morphology and discuss their possible phylogenetic affinities. Several larvae seem to represent the lineage of Stratiomyomorpha. A few others present characters unique to Xylophagidae (awl-flies), as well as to Athericidae (water sniper-flies), resulting in a chimeric morphology. Understanding the exact relationships of most of these specimens with a particular lineage remains challenging, since they differ considerably from any other known dipteran larvae and present some unique traits. Additionally, we report new specimens of Qiyia jurassica Chen et al., 2014, supposedly parasitic larvae, most likely representatives of Athericidae. These new findings offer valuable insights into the evolution of the early diversification of the brachyceran flies and underscore the importance of immature stages in understanding the evolutionary history and ecology of flies.

18.
Anat Rec (Hoboken) ; 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38567519

ABSTRACT

A new genus and two new species, Tholimantispa zuoae gen. et sp. nov. and Mantispidipterella curvis sp. nov. are described from the Upper Cretaceous of northern Myanmar amber collected in 2015. Tholimantispa zuoae gen. et sp. nov. is characterized by its distinct pterostigma, broad costal space, bifurcate humeral veinlets, and so forth, and Mantispidipterella curvis sp. nov. is different from Mantispidipterella longissima Liu, Lu et Zhang, 2017 in its ScP (subcosta posterior) distinctly curved at fusing point with RA (radius anterior), RP (radius posterior) abruptly and angularly curved at ra-rp (crossvein between RA and RP), AA3 (third branches of the anterior anal vein) present. The new fossil species enrich the diversity of Dipteromantispidae in the Cretaceous.

19.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124201, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38579424

ABSTRACT

One special variety of Burmese amber is "chameleon" amber, named for the bluish-green colour that appears to float on its surface. This material is found in the famous Tengchong market in Yunnan Province, China's largest Burmese amber market. Its bodycolour ranges from golden brown to brownish-red or even red. When exposed to sunlight or strong white light against a black background, its surface shows a uniform green colour. This research presents the gemological properties, spectral characteristics and organic components of Burmese 'chameleon' amber. Three-dimensional (3D) fluorescence spectra showed that Burmese 'chameleon' amber had fluorescence centres near 433, 465 and 470 nm, and the excitation wavelengths of the fluorescence centres of Burmese 'chameleon' amber were shifted from the ultraviolet region (380 ± 10 nm) to the visible region (410 ± 10 nm), with the emission wavelengths concentrated at the bluish-green region. Through the colour simulation and superimposition, the phenomenon of floating bluish-green fluorescence colour of Burmese 'chameleon' amber is not only derived from bluish-green fluorescence centres, but also enhanced by the mixture of surface fluorescence and its bodycolour. Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) analysis demonstrated the variety of aromatic compounds in Burmese 'chameleon' amber was related to geological process and the presence of fluorescence components. The high-performance liquid chromatography-fluorescence detector obtained some fluorescent aromatics, particularly benzo[a]anthracene with yellowish-green fluorescence, which is responsible for the fluorescence characteristics of Burmese 'chameleon' amber.

20.
Proc Biol Sci ; 291(2020): 20232546, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38565153

ABSTRACT

Fossilized mating insects are irreplaceable material for comprehending the evolution of the mating behaviours and life-history traits in the deep-time record of insects as well as the potential sexual conflict. However, cases of mating pairs are particularly rare in fossil insects, especially aquatic or semi-aquatic species. Here, we report the first fossil record of a group of water striders in copulation (including three pairs and a single adult male) based on fossils from the mid-Cretaceous of northern Myanmar. The new taxon, Burmogerris gen. nov., likely represents one of the oldest cases of insects related to the marine environment, such as billabongs formed by the tides. It exhibits conspicuous dimorphism associated with sexual conflict: the male is equipped with a specialized protibial comb as a grasping apparatus, likely representing an adaptation to overcome female resistance during struggles. The paired Burmogerris show smaller males riding on the backs of the females, seemingly recording a scene of copulatory struggles between the sexes. Our discovery reveals a mating system dominated by males and sheds light on the potential sexual conflicts of Burmogerris in the Cretaceous. It indicates the mating behaviour remained stable over long-term geological time in these water-walking insects.


Subject(s)
Amber , Life History Traits , Animals , Female , Male , Insecta , Reproduction , Copulation , Fossils , Myanmar
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