Identification and Functional Analysis of Temperate Siphoviridae Bacteriophages of Acinetobacter baumannii

Acinetobacter baumannii is an opportunistic pathogen that presents a serious clinical challenge due to its increasing resistance to all available antibiotics. Phage therapy has been introduced recently to treat antibiotic-incurable A. baumannii infections. In search for new A. baumannii specific bacteriophages, 20 clinical A. baumannii strains were used in two pools in an attempt to enrich phages from sewage. The enrichment resulted in induction of resident prophage(s) and three temperate bacteriophages, named vB_AbaS_fEg-Aba01, vB_AbaS_fLi-Aba02 and vB_AbaS_fLi-Aba03, all able to infect only one strain (#6597) of the 20 clinical strains, were isolated. Morphological characteristics obtained by transmission electron microscopy together with the genomic information revealed that the phages belong to the family Siphoviridae. The ca. 35 kb genomic sequences of the phages were >99% identical to each other. The linear ds DNA genomes of the phages contained 10 nt cohesive end termini, 52–54 predicted genes, an attP site and one tRNA gene each. A database search revealed an >99% identical prophage in the genome of A. baumannii strain AbPK1 (acc. no. CP024576.1). Over 99% identical prophages were also identified from two of the original 20 clinical strains (#5707 and #5920) and both were shown to be spontaneously inducible, thus very likely being the origins of the isolated phages. The phage vB_AbaS_fEg-Aba01 was also able to lysogenize the susceptible strain #6597 demonstrating that it was fully functional. The phages showed a very narrow host range infecting only two A. baumannii strains. In conclusion, we have isolated and characterized three novel temperate Siphoviridae phages that infect A. baumannii.

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Discovery of Three Toxic Proteins of Klebsiella Phage fHe-Kpn01

Viruses ◽

10.3390/v12050544 ◽

2020 ◽

Vol 12 (5) ◽

pp. 544

Author(s):

Cindy M. Spruit ◽

Anu Wicklund ◽

Xing Wan ◽

Mikael Skurnik ◽

Maria I. Pajunen

Keyword(s):

Virulence Genes ◽

Phage Therapy ◽

Sewage Water ◽

Lytic Phage ◽

Gene Products ◽

Proteomics Analysis ◽

Narrow Host Range ◽

Extended Spectrum Beta Lactamase ◽

The Family ◽

Associated Proteins

The lytic phage, fHe-Kpn01 was isolated from sewage water using an extended-spectrum beta-lactamase-producing strain of Klebsiella pneumoniae as a host. The genome is 43,329 bp in size and contains direct terminal repeats of 222 bp. The genome contains 56 predicted genes, of which proteomics analysis detected 29 different proteins in purified phage particles. Comparison of fHe-Kpn01 to other phages, both morphologically and genetically, indicated that the phage belongs to the family Podoviridae and genus Drulisvirus. Because fHe-Kpn01 is strictly lytic and does not carry any known resistance or virulence genes, it is suitable for phage therapy. It has, however, a narrow host range since it infected only three of the 72 tested K. pneumoniae strains, two of which were of capsule type KL62. After annotation of the predicted genes based on the similarity to genes of known function and proteomics results on the virion-associated proteins, 22 gene products remained annotated as hypothetical proteins of unknown function (HPUF). These fHe-Kpn01 HPUFs were screened for their toxicity in Escherichia coli. Three of the HPUFs, encoded by the genes g10, g22, and g38, were confirmed to be toxic.

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Occurrence of galls in Microgramma mortoniana (Polypodiopsida: Polypodiaceae) from a subtropical forest, Brazil

Lilloa ◽

10.30550/j.lil/2020.57.1/5 ◽

2020 ◽

pp. 72-80

Author(s):

Carlos R. Lehn ◽

Marcelo D. Arana ◽

Gerson Azulim Müller ◽

Edmilson Bianchini

Keyword(s):

Host Plants ◽

Deciduous Forest ◽

Morphological Characteristics ◽

Normal Growth ◽

Plant Tissues ◽

Sampling Effort ◽

Forest Fragment ◽

Narrow Host Range ◽

The Family ◽

Different Types

The galls are structures formed of plant tissues in response to the activity of different types of organisms, especially by insects. As a consequence of an intimate relationship with their host plants, most of these insects have a very narrow host range. In this study we report the occurrence of galls on Microgramma mortoniana. Morphological characteristics and field observations are presented. The study was carried out in a seasonal semi-deciduous forest fragment, located in the São João do Oeste municipality, Santa Catarina, southern Brazil. The galls present a fusiform shape and similar indument to the rhizome, in a higher density. In the region of occurrence of the galls, a widening of the rhizome was observed, reaching an average of 9 mm (±1mm), whereas in a rhizome with normal growth the width is 4 (±1 mm). The gall is unicameral, with the following dimensions: 7 mm (±1 mm) x 2 (±1 mm). The larvae observed into the chamber are about 0,7 mm long, being representative of the family Tortricidae (Lepidoptera). In all cases, the rhizomes with galls do not presented continuous development and, consequently, the rhizome has its limit of growth defined by the occurrence of the gall. The results indicate that a greater sampling effort of fern galls in the Neotropics is needed, contributing to the knowledge about the distribution of the galls on ferns lineages.

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Draft Genome Sequences of Six Multidrug-Resistant Clinical Strains of Acinetobacter baumannii, Isolated at Two Major Hospitals in Kuwait

Genome Announcements ◽

10.1128/genomea.00264-18 ◽

2018 ◽

Vol 6 (16) ◽

pp. e00264-18 ◽

Cited By ~ 2

Author(s):

Kother Nasser ◽

Abu Salim Mustafa ◽

Mohd Wasif Khan ◽

Prashant Purohit ◽

Inaam Al-Obaid ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Draft Genome ◽

Opportunistic Pathogen ◽

Multidrug Resistant ◽

Genome Sequences ◽

Content Type ◽

Health Care Settings ◽

Clinical Strains ◽

Global Health Care ◽

Genome Assemblies

ABSTRACT Acinetobacter baumannii is an important opportunistic pathogen in global health care settings. Its dissemination and multidrug resistance pose an issue with treatment and outbreak control. Here, we present draft genome assemblies of six multidrug-resistant clinical strains of A. baumannii isolated from patients admitted to one of two major hospitals in Kuwait.

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Distribution of Four Biofilm Associated Gene among A. baumannii by in Silico-PCR

Journal of Pharmaceutical Research International ◽

10.9734/jpri/2021/v33i57b34062 ◽

2021 ◽

pp. 317-324

Author(s):

J. D. Monesh Babu ◽

A. S. Smiline Girija ◽

P. Sankar Ganesh ◽

J. Vijayashree Priyadharsini

Keyword(s):

Acinetobacter Baumannii ◽

In Silico ◽

Biofilm Formation ◽

Experimental Validation ◽

Pcr Amplification ◽

Opportunistic Pathogen ◽

Clinical Strains ◽

Oral Biofilms ◽

Different Strains ◽

In Silico Pcr

Background: A.baumannii is an opportunistic pathogen known for its efficient biofilm formation that is attributed for its virulence. Acinetobacter baumannii is an inhabitant of oral biofilms as well. Many gene operons are involved in the biofilm formation that need to be monitored frequently. Aim: The aim of the present study was to detect the distribution of four biofilm associated genes among A.baumannii. Materials and Methods: Four biofilm forming genes viz., bfms, ptk, pgaB, and fimH of A.baumannii were selected. Forward and reverse primers of those four genes were used for in-silico PCR amplification. 19 strains of A.baumannii set as default on the server were chosen and the amplicon bands were observed Results: The present investigation documents the distribution of four vital biofilm associated gene among 19 different strains of A.baumannii among which bfms was distributed at a higher frequency followed by pgaB and ptk Conclusion: The finding of the study suggests the presence of pgaB, bfms, ptk among the 19 different strains of A.baumannii. However further experimental validation must be done to frequently monitor the presence of the genes among the clinical strains of A.baumannii.

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Pollen morphology of some species belonging to Codonoprasum and Allium sections of Allium (Liliaceae-Alliaceae) genus

Biologia ◽

10.2478/s11756-006-0075-z ◽

2006 ◽

Vol 61 (4) ◽

Cited By ~ 7

Author(s):

Ümmügülsüm Güler ◽

Sevil Pehlivan

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Pollen Morphology ◽

Morphological Characteristics ◽

Transmission Electron ◽

Exine Ornamentation ◽

The Family ◽

Tem Transmission Electron Microscopy ◽

Scanning Electron ◽

Section Level

AbstractPollen morphology of 14 Allium L. species grown in Turkey, that belong to the sections Codonoprasum and Allium, were investigated under LM (light microscopy) and by SEM (scanning electron microscopy). However, the pollens of 5 species were investigated under TEM (transmission electron microscopy). Detailed pollen morphological characteristics are given for Allium in the family on the basis of the results presented here together with data from the literature. The genera Allium homogeneous in both aperture type and exine ornamentation. It is suggested that some palynological characters, such as aperture type and the presence of an operculum, could be of taxonomic value at the section level.

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High frequency of blaPER-1 gene in clinical strains of Acinetobacter baumannii and its association with quorum sensing and virulence factors

Gene Reports ◽

10.1016/j.genrep.2021.101232 ◽

2021 ◽

Vol 24 ◽

pp. 101232

Author(s):

Fariba Naeimi Mazraeh ◽

Alka Hasani ◽

Javid Sadeghi ◽

Hossein Samadi Kafil ◽

Mohammad Hossein Soroush Barhaghi ◽

...

Keyword(s):

Quorum Sensing ◽

Acinetobacter Baumannii ◽

Virulence Factors ◽

High Frequency ◽

Clinical Strains

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Acinetobacter baumannii Infections in Hospitalized Patients, Treatment Outcomes

Antibiotics ◽

10.3390/antibiotics10060630 ◽

2021 ◽

Vol 10 (6) ◽

pp. 630

Author(s):

Diaa Alrahmany ◽

Ahmed F. Omar ◽

Gehan Harb ◽

Wasim S. El El Nekidy ◽

Islam M. Ghazi

Keyword(s):

Acinetobacter Baumannii ◽

Treatment Outcomes ◽

Antibiotic Treatment ◽

Financial Burden ◽

Opportunistic Pathogen ◽

Hospitalized Patients ◽

Treatment Regimens ◽

Serious Infections ◽

Optimal Approach ◽

Selection Of

Background Acinetobacter baumannii (AB), an opportunistic pathogen, could develop into serious infections with high mortality and financial burden. The debate surrounding the selection of effective antibiotic treatment necessitates studies to define the optimal approach. This study aims to compare the clinical outcomes of commonly used treatment regimens in hospitalized patients

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A systematic revision of Capparaceae and Cleomaceae in Egypt: an evaluation of the generic delimitations of Capparis and Cleome using ecological and genetic diversity

Journal of Genetic Engineering and Biotechnology ◽

10.1186/s43141-020-00069-z ◽

2020 ◽

Vol 18 (1) ◽

Author(s):

Mohamed Abd. S. El zayat ◽

Mahmoud El Sayd Ali ◽

Mohamed Hamdy Amar

Keyword(s):

Genetic Diversity ◽

Morphological Characteristics ◽

Systematic Position ◽

Diversity Analysis ◽

Polymorphic Markers ◽

Ecological Distribution ◽

Specific Group ◽

Systematic Revision ◽

Dna Evidence ◽

The Family

Abstract Background The Capparaceae family is commonly recognized as a caper, while Cleomaceae represents one of small flowering family within the order Brassicales. Earlier, Cleomaceae was included in the family Capparaceae; then, it was moved to a distinct family after DNA evidence. Variation in habits and a bewildering array of floral and fruit forms contributed to making Capparaceae a “trash-basket” family in which many unrelated plants were placed. Indeed, family Capparaceae and Cleomaceae are in clear need of more detailed systematic revision. Results Here, in the present study, the morphological characteristics and the ecological distribution as well as the genetic diversity analysis among the twelve species of both Capparaceae and Cleomaceae have been determined. The genetic analysis has been checked using 15 ISSR, 30 SRAP, and 18 ISTR to assess the systematic knots between the two families. In order to detect the molecular phylogeny, a comparative analysis of the three markers was performed based on the exposure of discriminating capacity, efficiency, and phylogenetic heatmap. Our results indicated that there is a morphological and ecological variation between the two families. Moreover, the molecular analysis confirmed that ISTR followed by SRAP markers has superior discriminating capacity for describing the genetic diversity and is able to simultaneously distinguish many polymorphic markers per reaction. Indeed, both the PCA and HCA data have drawn a successful annotation relationship in Capparaceae and Cleome species to evaluate whether the specific group sort individual or overlap groups. Conclusion The outcomes of the morphological and ecological characterization along with the genetic diversity indicated an insight solution thorny interspecies in Cleome and Gynandropsis genera as a distinct family (Cleomaceae) and the other genera (Capparis, Cadaba, Boscia, and Maerua) as Capparaceae. Finally, we recommended further studies to elucidate the systematic position of Dipterygium glaucum.

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Larval development of Metapenaeopsis barbata (de Haan, 1844) (Crustacea: Decapoda: Penaeidae)

Marine and Freshwater Research ◽

10.1071/mf93077 ◽

1997 ◽

Vol 48 (5) ◽

pp. 401 ◽

Cited By ~ 4

Author(s):

Jesse D. Ronquillo ◽

Toshio Saisho

Keyword(s):

Morphological Characteristics ◽

Larval Feeding ◽

Feeding Apparatus ◽

Filter Feeder ◽

Closely Related Species ◽

Larval Stages ◽

Chaetoceros Gracilis ◽

The Family ◽

Gravid Females ◽

Natural Means

Gravid females of Metapenaeopsis barbata spawned in the laboratory by natural means and the larvae were reared from hatching to postlarval stage at 27·0–29·8˚C and 33·5–34·5 g kg -1 salinity. The larvae metamorphosed into first postlarvae, with a survival rate of up to 98·4%, after about 10 days following hatching and subsistence on only an algal diet of Tetraselmis tetrathele and Chaetoceros gracilis. Six naupliar stages, three protozoeal stages, three mysis stages and the first postlarval stage are described and illustrated. On the basis of morphological characteristics, larval stages of M. barbata can be distinguished from similar stages of closely related species in the family Penaeidae. As inferred from the morphology of the larval feeding apparatus, M. barbata is still a filter-feeder even at the first postlarval stage.

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Genetic and phenotypic analysis of the pathogenic potential of two novel Chlamydia gallinacea strains compared to Chlamydia psittaci

Scientific Reports ◽

10.1038/s41598-021-95966-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Marloes Heijne ◽

Martina Jelocnik ◽

Alexander Umanets ◽

Michael S. M. Brouwer ◽

Annemieke Dinkla ◽

...

Keyword(s):

Virulence Factors ◽

Opportunistic Pathogen ◽

Chlamydia Psittaci ◽

Phenotypic Analysis ◽

Pathogenic Potential ◽

The Family ◽

Chicken Eggs ◽

Sequence Types ◽

Insight Into ◽

Embryonated Chicken

AbstractChlamydia gallinacea is an obligate intracellular bacterium that has recently been added to the family of Chlamydiaceae. C. gallinacea is genetically diverse, widespread in poultry and a suspected cause of pneumonia in slaughterhouse workers. In poultry, C. gallinacea infections appear asymptomatic, but studies about the pathogenic potential are limited. In this study two novel sequence types of C. gallinacea were isolated from apparently healthy chickens. Both isolates (NL_G47 and NL_F725) were closely related to each other and have at least 99.5% DNA sequence identity to C. gallinacea Type strain 08-1274/3. To gain further insight into the pathogenic potential, infection experiments in embryonated chicken eggs and comparative genomics with Chlamydia psittaci were performed. C. psittaci is a ubiquitous zoonotic pathogen of birds and mammals, and infection in poultry can result in severe systemic illness. In experiments with embryonated chicken eggs, C. gallinacea induced mortality was observed, potentially strain dependent, but lower compared to C. psittaci induced mortality. Comparative analyses confirmed all currently available C. gallinacea genomes possess the hallmark genes coding for known and potential virulence factors as found in C. psittaci albeit to a reduced number of orthologues or paralogs. The presence of potential virulence factors and the observed mortality in embryonated eggs indicates C. gallinacea should rather be considered as an opportunistic pathogen than an innocuous commensal.

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