Read by QxMD icon Read


Torbjörn Bengtsson, Johanna Lönn, Hazem Khalaf, Eleonor Palm
Antimicrobial resistance needs to be tackled from new angles, and antimicrobial peptides could be future candidates for combating bacterial infections. This study aims to investigate in vitro the bactericidal effects of the lantibiotic gallidermin on Staphylococcus epidermidis and Staphylococcus aureus, possible cytotoxic effects and its impact on host-microbe interactions. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of gallidermin were determined, and cytotoxicity and proinflammatory effects of gallidermin on fibroblasts, red blood cells (RBCs) and in whole blood were investigated...
March 13, 2018: MicrobiologyOpen
Ashwini Dolle, Narasimhappagari Jagadeesh, Suman Bhaumik, Sunita Prakash, Himansu S Biswal, Konkallu Hanumae Gowd
RATIONALE: The modes of cleavages of lanthionine/methyllanthionine bridges under electron transfer dissociation (ETD) was investigated using synthetic and natural lantipeptides. Knowledge on the mass spectrometric fragmentation of lanthionine/methyllanthionine bridges may assist in the development of analytical methods for rapid discovery of new lantibiotics. Present study strengthens the advantage of ETD in the characterization of posttranslational modifications of peptides and proteins...
March 8, 2018: Rapid Communications in Mass Spectrometry: RCM
Sahar Hasim, David P Allison, Berlin Mendez, Abigail T Farmer, Dale A Pelletier, Scott T Retterer, Shawn R Campagna, Todd B Reynolds, Mitchel J Doktycz
The use of naturally occurring antimicrobial peptides provides a promising route to selectively target pathogenic agents and to shape microbiome structure. Lantibiotics, such as duramycin, are one class of bacterially produced peptidic natural products that can selectively inhibit the growth of other bacteria. However, despite longstanding characterization efforts, the microbial selectivity and mode of action of duramycin are still obscure. We describe here a suite of biological, chemical, and physical characterizations that shed new light on the selective and mechanistic aspects of duramycin activity...
2018: Frontiers in Microbiology
Manuel Montalbán-López, Jingjing Deng, Auke J van Heel, Oscar P Kuipers
Lantibiotics are ribosomally produced and posttranslationally modified peptides containing several lanthionine residues. They exhibit substantial antimicrobial activity against Gram-positive bacteria, including relevant pathogens. The production of the model lantibiotic nisin minimally requires the expression of the modification and export machinery. The last step during nisin maturation is the cleavage of the leader peptide. This liberates the active compound and is catalyzed by the cell wall-anchored protease NisP...
2018: Frontiers in Microbiology
Yasushi Ogasawara, Tohru Dairi
D-Amino acid residues have been identified in peptides from a variety of eukaryotes and prokaryotes. In microorganisms, UDP- N -acetylmuramic acid pentapeptide (UDP-MurNAc-L-Ala-D-Glu-meso-diaminopimelate-D-Ala-D-Ala), a unit of peptidoglycan, is a representative. During its biosynthesis, D-Ala and D-Glu are generally supplied by racemases from the corresponding isomers. However, we recently identified a unique unidirectional L-Glu epimerase catalyzing the epimerization of the terminal L-Glu of UDP-MurNAc-L-Ala-L-Glu...
2018: Frontiers in Microbiology
Nidhi Kakkar, Jessica G Perez, Wenshe R Liu, Michael C Jewett, Wilfred A van der Donk
Lantibiotics are ribosomally synthesized and post-translationally modified peptide natural products that contain thioether crosslinks formed by lanthionine and methyllanthionine residues. They exert potent antimicrobial activity against Gram-positive bacteria. We herein report production of analogues of two lantibiotics, lacticin 481 and nisin that contain non-proteinogenic amino acids using two different strategies involving amber stop codon suppression technology. These methods complement recent alternative approaches to incorporate non-proteinogenic amino acids into lantibiotics...
February 13, 2018: ACS Chemical Biology
Francesco DI Pierro, Paolo Risso, Elena Poggi, Anna Timitilli, Sara Bolloli, Maurizio Bruno, Egidio Caneva, Riccardo Campus, Alessandro Giannattasio
BACKGROUND: Previous trials, performed in subjects affected by recurrent streptococcal pharyngo-tonsillar infection, have shown that the use for 90 days of Streptococcus salivarius K12 (K12), an oral colonizing probiotic producing lantibiotic bacteriocins, reduces the occurrence of streptococcal and viral pharyngitis and acute otitis media (AOM). The aim was to evaluate the role of K12 in reducing the incidence of streptococcal and viral pharyngo-tonsillitis and AOM when administered in two separate trimesters, from October to December and then from April to June, in pediatric subjects with non-recurrent streptococcal infection...
January 11, 2018: Minerva Pediatrica
Jin Hee Jeong, Sung Chul Ha
Nisin is a lantibiotic, a family of polypeptides containing lanthionine with antimicrobial activity. Nisin-producing microorganisms require immunity proteins for self-protection from nisin itself. Lactococcus lactis, a microorganism that synthesizes nisin, has an integral NisFEG ABC transporter and NisI lipoprotein that function in the nisin immunity. Here, we present the crystal structure of the full length of NisI22-C, a lipid-free form of NisI, determined at 1.9 Å resolution. Similar to the NMR structures of N- and C-terminal domain of NisI, NisI22-C is composed of N- and C-terminal domains, both of which display a fold similar to that found in SpaI, a lipoprotein with immunity against subtilin in Bacillus subtilis The full length structure of NisI22-c reveals a large and deep cleft by the interdomain association, one side of which is occupied by the residues important for immunity...
January 8, 2018: Antimicrobial Agents and Chemotherapy
Li Zhang, Kunling Teng, Jian Wang, Zheng Zhang, Jie Zhang, Shutao Sun, Lili Li, Xiaopan Yang, Jin Zhong
Cerecidins are small lantibiotics from Bacillus cereus that were obtained using a semi-in vitro biosynthesis strategy and showed prominent antimicrobial activities against certain Gram-positive bacteria. However, the parental strain B. cereus As 1.1846 is incapable of producing cerecidins, most probably due to the transcriptional repression of the cerecidin gene cluster. Located in the cerecidin gene cluster, cerR encodes a putative response regulator protein that belongs to LuxR-family transcriptional regulators...
December 15, 2017: Applied and Environmental Microbiology
Giuseppe Gallo, Andrea Scaloni
Proteomics based on 2D-Difference In Gel Electrophoresis (2D-DIGE) coupled with mass spectrometry (MS) procedures can be considered a "gold standard" to determine quantitatively and comparatively protein abundances in cell extracts from different biological sources/conditions according to a gel-based approach. In particular, 2D-DIGE is used for protein specie separation, detection, and relative quantification, whenever tandem MS is used to obtain peptide sequence information that is managed according to bioinformatic procedures to identify the differentially represented protein species...
2018: Methods in Molecular Biology
Mengxin Geng, Leif Smith
Lanthipeptides are a class of ribosomally synthesized and post-translationally modified peptides. Lanthipeptides with antimicrobial activity are referred to as lantibiotics. Lantibiotics are generally active against Gram-positive bacteria. However, some modifications have expanded their activity toward Gram-negative bacteria. Furthermore, additional functions aside from antibacterial activities have been reported for lanthipeptides. Areas covered: This review provides a synopsis of current anthipeptide research for potential therapeutics...
February 2018: Expert Opinion on Drug Discovery
Sen Zheng, Jun-Ichi Nagao, Mami Nishie, Takeshi Zendo, Kenji Sonomoto
Lantibiotic nukacin ISK-1 is produced by Staphylococcus warneri ISK-1. The dual functional transporter NukT, an ABC transporter maturation and secretion protein, contributes to cleavage of the leader peptide from the prepeptide (modified NukA) and the final transport of nukacin ISK-1. NukT consists of an N-terminal peptidase domain (PEP), a C-terminal nucleotide-binding domain (NBD), and a transmembrane domain (TMD). In this study, NukT and its peptidase-inactive mutant were expressed, purified, and reconstituted into liposomes for analysis of their peptidase and ATPase activities...
November 22, 2017: Applied Microbiology and Biotechnology
Alireza Bakhtiary, Stephen A Cochrane, Pascal Mercier, Ryan T McKay, Mark Miskolzie, Clarissa S Sit, John C Vederas
Lacticin 3147 is a two peptide lantibiotc (LtnA1 and LtnA2) that displays nanomolar activity against many Gram-positive bacteria. Lacticin 3147 may exert its antimicrobial effect by several mechanisms. Isothermal titration calorimetry experiments show that only LtnA1 binds to the peptidoglycan precursor lipid II, which could inhibit peptidoglycan biosynthesis. An experimentally supported model of the resulting complex suggests that the key binding partners are the C-terminus of LtnA1 and pyrophosphate of lipid II...
December 13, 2017: Journal of the American Chemical Society
Cristina Brunati, Thomas T Thomsen, Eleonora Gaspari, Sonia Maffioli, Margherita Sosio, Daniela Jabes, Anders Løbner-Olesen, Stefano Donadio
Objectives: To characterize NAI-107 and related lantibiotics for their in vitro activity against Gram-negative pathogens, alone or in combination with polymyxin, and against non-dividing cells or biofilms of Staphylococcus aureus. NAI-107 was also evaluated for its propensity to select or induce self-resistance in Gram-positive bacteria. Methods: We used MIC determinations and chequerboard experiments to establish the antibacterial activity of the examined compounds against target microorganisms...
October 30, 2017: Journal of Antimicrobial Chemotherapy
Clemencia Chaves López, Annalisa Serio, Costanza Montalvo, Cristina Ramirez, José Angel Peréz Álvarez, Antonello Paparella, Dino Mastrocola, Maria Martuscelli
Nisin is a lantibiotic exhibiting antimicrobial activity against a wide range of Gram-positive bacteria, or some Gram-negative bacteria when used in combination with other preservative agents. The objective of the present work was to study the effect of nisin treatment on biogenic amines occurrence and shelf life of refrigerated (4 °C) vacuum packaged rainbow trout samples. For this purpose samples were divided in two batches: the experimental batch (CB-N), consisting of samples immersed in sterilized broth formulated with soy milk 1...
September 2017: Journal of Food Science and Technology
Jens Reiners, Marcel Lagedroste, Katja Ehlen, Selina Leusch, Julia Zaschke-Kriesche, Sander H J Smits
Lantibiotics are (methyl)-lanthionine-containing antimicrobial peptides produced by several Gram-positive bacteria. Some human pathogenic bacteria express specific resistance proteins that counteract this antimicrobial activity of lantibiotics. In Streptococcus agalactiae COH1 resistance against the well-known lantibiotic nisin is conferred by, the nisin resistance protein (NSR), a two-component system (NsrRK) and a BceAB-type ATP-binding cassette (ABC) transporter (NsrFP). The present study focuses on elucidating the function of NsrFP via its heterologous expression in Lactococcus lactis...
2017: Frontiers in Microbiology
J-E Park, H-R Kim, S-Y Park, S-K Choi, S-H Park
AIMS: To analyse the function of a putative lantibiotic gene cluster of Paenibacillus polymyxa E681 and to characterize its product, paenilan. METHODS AND RESULTS: Comparative analysis of the lantibiotic gene cluster of E681 revealed that the cluster, consisting of 11 open reading frames, is involved in the biosynthesis of a class I lantibiotic. The pnlA gene encoding the prepeptide PnlA was identified and P. polymyxa strain EPT14 producing only paenilan was constructed by knockout of the other five antibiotic biosynthetic gene clusters of E681...
September 4, 2017: Journal of Applied Microbiology
Bo Dong, Yunhai Yi, Lifeng Liang, Qiong Shi
Antimicrobial peptides (AMPs) are a group of small peptides, which are secreted by almost all creatures in nature. They have been explored in therapeutic and agricultural aspects as they are toxic to many bacteria. A considerable amount of work has been conducted in analyzing 16S and metagenomics of the gastrointestinal (GI) microbiome of grass carp (Ctenopharyngodon idellus). However, these datasets are still untapped resources. In this present study, a homologous search was performed to predict AMPs from our newly generated metagenome of grass carp...
August 30, 2017: Toxins
Diane Hatziioanou, Cristina Gherghisan-Filip, Gerhard Saalbach, Nikki Horn, Udo Wegmann, Sylvia H Duncan, Harry J Flint, Melinda J Mayer, Arjan Narbad
A novel lanC-like sequence was identified from the dominant human gut bacterium Blautia obeum strain A2-162. This sequence was extended to reveal a putative lantibiotic operon with biosynthetic and transport genes, two sets of regulatory genes, immunity genes, three identical copies of a nisin-like lanA gene with an unusual leader peptide, and a fourth putative lanA gene. Comparison with other nisin clusters showed that the closest relationship was to nisin U. B. obeum A2-162 demonstrated antimicrobial activity against Clostridium perfringens when grown on solid medium in the presence of trypsin...
August 31, 2017: Microbiology
Aleksandra Tymoszewska, Dzung B Diep, Paulina Wirtek, Tamara Aleksandrzak-Piekarczyk
Mannose phosphotransferase system (Man-PTS) is the main mannose permease in bacteria but it is also a known receptor for subclass IIa bacteriocins (pediocin-like group) as well as subclass IId lactococcin A (LcnA) and lactococcin B (LcnB) (LcnA-like group). Subclass IIa bacteriocins exhibit a strong activity against Listeria spp. but they are not against Lactococcus spp. In contrast, the LcnA-like bacteriocins act only against Lactococcus lactis strains. Garvicin Q (GarQ) is a subclass IId bacteriocin with minor similarity to LcnA-like bacteriocins and a relatively broad antimicrobial spectrum including, among others, Listeria and Lactococcus spp...
August 21, 2017: Scientific Reports
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"