scholarly journals Diversity of Antimicrobial Peptides in Three Partially Sympatric Frog Species in Northeast Asia and Implications for Evolution

Genes ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 158
Author(s):  
Qing Wang ◽  
Rui Xia ◽  
Jing Jing Ji ◽  
Qian Zhu ◽  
Xiao Ping Li ◽  
...  
Keyword(s):  
Antimicrobial Peptides ◽  
Habitat Preferences ◽  
Northeast Asia ◽  
Significant Negative Correlation ◽  
Evolution System ◽  
Charge Balance ◽  
Antimicrobial Efficiency ◽  
Habitat Variation ◽  
Frog Species ◽  
Diversification Mechanism

Antimicrobial peptides (AMPs) are evolutionarily ancient molecules that play an essential role in innate immunity across taxa from invertebrates to vertebrates. The evolution system of AMP system has not been well explained in the literature. In this study, we cloned and sequenced AMP transcriptomes of three frog species, namely Rana dybowskii, Rana amurensis, and Pelophylax nigromaculatus, which are partially sympatric in northeast Asia, but show different habitat preferences. We found that each species contained 7 to 14 families of AMPs and the diversity was higher in species with a large geographic range and greater habitat variation. All AMPs are phylogenetically related but not associated with the speciation process. Most AMP genes were under negative selection. We propose that the diversification and addition of novel functions and improvement of antimicrobial efficiency are facilitated by the expansion of family members and numbers. We also documented significant negative correlation of net charges and numbers of amino acid residues between the propiece and mature peptide segments. This supports the Net Charge Balance Hypothesis. We propose the Cut Point Sliding Hypothesis as a novel diversification mechanism to explain the correlation in lengths of the two segments.

scholarly journals Skin secretions of Rana saharica frogs reveal antimicrobial peptides esculentins-1 and -1B and brevinins-1E and -2EC with novel insulin releasing activity

2006 ◽  
Vol 188 (1) ◽  
pp. 1-9 ◽  
Author(s):  
L Marenah ◽  
P R Flatt ◽  
D F Orr ◽  
C Shaw ◽  
Y H A Abdel-Wahab
Keyword(s):  
Antimicrobial Peptides ◽  
Insulin Release ◽  
Skin Surface ◽  
Bioactive Molecules ◽  
Peptide Family ◽  
Insulin Secretagogues ◽  
Frog Species ◽  
Molecular Masses ◽  
Skin Secretions ◽  
Toxic Peptides

Skin secretions of Rana saharica were evaluated for the isolation and characterisation of novel insulinotropic peptides. Crude secretions obtained from young adult frogs by mild electrical stimulation of the dorsal skin surface were purified by reverse phase HPLC yielding 80 fractions. In acute 20-min incubations with glucose responsive BRIN-BD11 cells, fractions 36–43, 46–54 and 57–63 significantly stimulated insulin release by 2- to 8-fold compared with 5.6 mM glucose alone. Pooled fractions in the latter two bands were rechromatographed to reveal 9 homogenous peaks, which elicited significant 1.3- to 3.5-fold increases in insulin release (P < 0.05). Structural analysis of the most potent non-toxic peptides was performed by mass spectrometry and automated Edman degradation. This revealed four major insulin-releasing peaks with molecular masses of 2676.9 Da, 3519.3 Da, 4920.4 Da and 4801.2 Da respectively. These peptides were found to be identical to brevinin-1E, brevinin-2EC, esculentin-1 and esculentin-1B, which belong to the group of antimicrobial peptides isolated from skin secretions of various Rana frog species. Preliminary studies on the mechanism underlying the insulinotropic actions of esculentins-1 and -1B suggested possible involvement of both cyclic AMP–protein kinase A and –C-dependent G-protein sensitive pathways. These data indicate that the skin secretions of Rana saharica frogs contain bioactive molecules with significant insulin-releasing activity. Relatives of the brevinin/esculentin peptide family merit further investigation as novel insulin secretagogues.

scholarly journals Construction and Characterizations of Antibacterial Surfaces Based on Self-Assembled Monolayer of Antimicrobial Peptides (Pac-525) Derivatives on Gold

Coatings ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1014
Author(s):  
Zijiao Zhang ◽  
Ni Kou ◽  
Weilong Ye ◽  
Shuo Wang ◽  
Jiaju Lu ◽  
...  
Keyword(s):  
Antimicrobial Peptides ◽  
Self Assembly ◽  
The Self ◽  
Self Assembled Monolayer ◽  
E Coli ◽  
Antimicrobial Efficiency ◽  
Gold Substrates ◽  
Self Assembled ◽  
Antibacterial Surfaces

Background: Infection that is related to implanted biomaterials is a serious issue in the clinic. Antimicrobial peptides (AMPs) have been considered as an ideal alternative to traditional antibiotic drugs, for the treatment of infections, while some problems, such as aggregation and protein hydrolysis, are still the dominant concerns that compromise their antimicrobial efficiency in vivo. Methods: In this study, antimicrobial peptides underwent self-assembly on gold substrates, forming good antibacterial surfaces, with stable antibacterial behavior. The antimicrobial ability of AMPs grafted on the surfaces, with or without glycine spaces or a primer layer, was evaluated. Results: Specifically, three Pac-525 derivatives, namely, Ac-CGn-KWRRWVRWI-NH2 (n = 0, 2, or 6) were covalently grafted onto gold substrates via the self-assembling process for inhibiting the growth of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Furthermore, the alkanethiols HS(CH)10SH were firstly self-assembled into monolayers, as a primer layer (SAM-SH) for the secondary self-assembly of Pac-525 derivatives, to effectively enhance the bactericidal performance of the grafted AMPs. The -(CH)10-S-S-G6Pac derivative was highly effective against S. aureus and E. coli, and reduced the viable amount of E. coli and S. aureus to 0.4% and 33.2%, respectively, after 24 h of contact. In addition, the immobilized AMPs showed good biocompatibility, promoting bone marrow stem cell proliferation. Conclusion: the self-assembled monolayers of the Pac-525 derivatives have great potential as a novel therapeutic method for the treatment of implanted biomaterial infections.

Seasonal dynamics of Bythonomus lemani and Bothrioneurum vejdovskyanum (Oligochaeta, Annelida) in relation to environmental variables

Biologia ◽  
2006 ◽  
Vol 61 (5) ◽  
Author(s):  
Jana Schenková ◽  
Jan Helešic ◽  
Jiří Jarkovský
Keyword(s):  
Seasonal Dynamics ◽  
Environmental Variables ◽  
Habitat Preferences ◽  
Oxygen Demand ◽  
Significant Negative Correlation ◽  
Life Cycles ◽  
Reproduction Cycle ◽  
Influence Of Water ◽  
One Year ◽  
First Time

AbstractThe seasonal dynamics of Bythonomus lemani (Lumbriculidae) were studied for the first time and the knowledge of Bothrioneurum vejdovskyanum (Tubificidae) was extended based on four quantitative samples of oligochaetes taken monthly in the Rokytná River (Czech Republic) during a two-year study (April 1999–April 2001). The influence of water temperature, velocity, depth, discharge, pH, conductivity, dissolved oxygen amount and biochemical oxygen demand (BOD) on their life cycles was evaluated. Habitat preferences of the juvenile and adult stages were recorded. Time series analysis was used to determine the worm densities, seasonality and trends. For Byth. lemani one distinct reproduction cycle per year was found and this was regulated by temperature, while Both. vejdovskyanum showed a one-year cycle not significantly dependent on measured environmental variables. The overall trend was an increase in density for Byth. lemani and a decrease in density for Both. vejdovskyanum. Byth. lemani showed a significant negative correlation between the trend of its density and BOD concentration.

Seasonal Habitat Preferences and Response to Water Quality Parameters of Tree Frog Species in a Neotropical Wetland

Wetlands ◽  
2021 ◽  
Vol 41 (5) ◽  
Author(s):  
Andrea Caballero-Gini ◽  
Diego Bueno-Villafañe ◽  
Marcela Ferreira ◽  
Lía Romero ◽  
Lucas Cañete ◽  
...  
Keyword(s):  
Water Quality ◽  
Habitat Preferences ◽  
Quality Parameters ◽  
Water Quality Parameters ◽  
Tree Frog ◽  
Frog Species ◽  
Response To Water

scholarly journals The PhoQ-Activating Potential of Antimicrobial Peptides Contributes to Antimicrobial Efficacy and Is Predictive of the Induction of Bacterial Resistance

2007 ◽  
Vol 51 (12) ◽  
pp. 4374-4381 ◽  
Author(s):  
Jason Kindrachuk ◽  
Nicole Paur ◽  
Carla Reiman ◽  
Erin Scruten ◽  
Scott Napper
Keyword(s):  
Antimicrobial Peptides ◽  
Bacterial Resistance ◽  
Immune Defense ◽  
Minimal Bactericidal Concentration ◽  
Adaptive Responses ◽  
Bacterial Strains ◽  
Concentration Data ◽  
Antimicrobial Efficiency ◽  
Novel Strategy ◽  
Therapeutic Administration

ABSTRACT Antimicrobial peptides (AMPs) are among the leading candidates to replace antibiotics which have been rendered ineffective by the evolution of resistant bacterial strains. Concerns do exist, however, that the therapeutic administration of AMPs may also select for resistant strains but with much more dire consequences, as these peptides represent an endogenous and essential component of host immune defense. The recent demonstration that AMPs function as ligands for the bacterial sensory kinase PhoQ for the initiation of virulence and adaptive responses lends credence to these concerns. While the ability to serve as PhoQ ligands suggests that the therapeutic administration of AMPs could (i) exacerbate infections by promoting bacterial virulence and (ii) select resistant mutants by encouraging adaptive behaviors, it also provides a rational basis for AMP selection and optimization. Here, we demonstrate that derivatives of a representative AMP have differential abilities to serve as PhoQ ligands and that this correlates with the ability to induce bacterial adaptive responses. We propose that PhoQ-activating potential is a logical parameter for AMP optimization and introduce a novel strategy for the treatment of minimal bactericidal concentration data that permits the discrimination and quantification of the contributions of PhoQ-activating potential and direct antimicrobial activity to net antimicrobial efficiency.

Photographic Field Guide to Australian Frogs

2021 ◽  
Author(s):  
Mark Sanders
Keyword(s):  
Habitat Preferences ◽  
Skin Texture ◽  
Diagnostic Features ◽  
Field Guide ◽  
Level Of Confidence ◽  
Strong Focus ◽  
The World ◽  
Eye Colour ◽  
Frog Species ◽  
High Level

Australia is home to more than 240 species of frogs, many of which cannot be found anywhere else in the world. The Photographic Field Guide to Australian Frogs provides readers with the tools to confidently identify 242 species and five recognised subspecies. It includes detailed information on the distribution, habitat preferences and call of each frog species, as well as fully illustrated keys to genera to assist with identification. Multiple photographs of each species show variation in colour and pattern as well as features used for identification such as thigh colouration, skin texture, belly colour and patterning, eye colour and extent of webbing between the toes. With a strong focus on illustrating variation and key diagnostic features, this guide will enable frog enthusiasts, environmental professionals and research scientists to identify Australian frog species with a high level of confidence.

scholarly journals Cytotaxonomic Study of Hypodematium (Hypodematiaceae) from China

Phytotaxa ◽  
2014 ◽  
Vol 161 (2) ◽  
pp. 101 ◽  
Author(s):  
Renxiang Wang ◽  
Wen Shao ◽  
Ling Liu
Keyword(s):  
Chromosome Number ◽  
Chromosome Numbers ◽  
Habitat Preferences ◽  
Northeast Asia ◽  
Basic Chromosome Number ◽  
Basic Chromosome ◽  
Dry Conditions ◽  
Diakinesis Stage ◽  
First Time ◽  
Meiosis I

Chromosome numbers and reproductive biology of nine species of the fern genus Hypodematium (Hypodematiaceae) from China were investigated. The chromosome numbers of eight species are reported here for the first time: H. daochengensis n=41 (41 II); H. fordii n=40 (40 II), n=80 (40 II+40 I), 2n=120; H. glanduloso-pilosum n=41 (41 II), 2n=82, 2n=123; H. gracile n=41 (41 II); H. hirsutum n= 41 (41 II); H. microleptoides n=41 (41 II); H. sinense n= 40 (40 II) and H. squamuloso-pilosum n=41 (41 II). Two cytotypes, n=82 (41 II+41 I) and 2n=123 in H. crenatum, are reported for the first time.  Our results showed that the species with these cytotypes are agamospermous triploids: H. crenatum n = 82 (41 II +41 I), H. glanduloso-pilosum n = 82 (41 II +41 I) and H. fordii n = 80 (40 II +40 I), based on the unequal size and presence of aborted spores in the sporangium, and the allotriploid hybrid chromosomes in the spore mother cell at the diakinesis stage of meiosis I. The remaining species are sexual diploids and tetraploids, based on the chromosome number n = 41 and n =82 at the diakinesis stage of meiosis I of spore mother cells. The relationships among habitat preferences, frond hairs and reproductive modes in Hypodematium are discussed and illustrated. It appears that plants with large fronds and sparse, thin hairs, living in humid and shady places undergo sexual reproduction, while small plants living in sunny and dry conditions with thick hairs undergo agamospermous reproduction. The distribution pattern and basic chromosome number all indicated the basic chromosome number x= 41 was plesiomorphic, whereas x=40 was apomorphic. Chromosome aneuploid changes occurred in this genus. The distribution of the sexual diploids and tetraploids and agamospermous triploids suggests that the genus might have originated in the Himalayas and dispersed from there to northeast Asia and Japan.

Antimicrobial peptides in COPD

Pneumologie ◽  
2009 ◽  
Vol 63 (S 01) ◽  
Author(s):  
G Günther ◽  
E Andresen ◽  
J Bullwinkel ◽  
C Lange ◽  
H Heine
Keyword(s):  
Antimicrobial Peptides
Sign in / Sign up

Export Citation Format

Share Document