BHU Institutional Repository :: Browsing by Author "Saraf, Aniket"

Browsing by Author "Saraf, Aniket"

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Circumscription of Fulbrightiella gen. nov. and Sherwoodiella gen. nov., Two Novel Genera in the Calotrichaceae (Nostocales, Cyanobacteria)
(John Wiley and Sons Inc, 2023) Kumar, Naresh; Saraf, Aniket; Pal, Sagarika; Mishra, Deeksha; Singh, Prashant; Johansen, Jeffrey R.
Three novel strains in Calotrichaceae from tropical habitats were isolated and characterized with regard to their morphology, phylogenetic placement, and secondary structures of conserved domains in the 16S-23S internal transcribed spacer (ITS). The strains fell into two clades formerly identified as Calothrix from freshwater and brackish habitats. Based on both morphology and ecology, they differed from the type species of Calothrix, C. confervicola, which is marine, has wide trichomes with short cells, and narrows abruptly to a hyaline hair. The first clade grouped species with heteropolar filaments widened at the base and narrowed gradually toward the apex but not ending in a hair, with basal heterocytes that are formed in series as the apically placed heterocytes senesce; this clade is being named Fulbrightiella gen. nov., with two named species, F. bharadwajae sp. nov. and F. oahuensis sp. nov. The second clade was comprised of a single species with isopolar trichomes that are untapering as hormogonia, but which widen midfilament and taper toward both ends following growth. These trichomes develop pairs of heterocyte mid-filament, causing fragmentation into heteropolar trichomes with basal heterocytes and ends that taper, but not to a hair. This clade consists of a single species at present, Sherwoodiella mauiensis. With this action, four clades in the Calotrichaceae have been named: Macrochaete, Dulcicalothrix, Fulbrightiella, and Sherwoodiella. Calothrix sensu stricto is truly marine, morphologically distinct, and unsequenced; finding and sequencing the generitype for Calothrix remains as the most important and unfinished task in the revision of the Calotrichaceae. � 2022 The Authors. Journal of Phycology published by Wiley Periodicals LLC on behalf of Phycological Society of America.
Constrictifilum karadense gen. et sp. nov., a new Nostocalean genus from Maharashtra, India
(Oxford University Press, 2021) Chavadar, Mahesh; Saraf, Aniket; Suradkar, Archana; Mishra, Deeksha; Kumar, Naresh; Singh, Prashant
A freshwater dwelling cyanobacterium (strain MKW3) was isolated from a sample collected from a water logged sugarcane field located in Malkapur, Karad, Maharashtra, India, and was characterized using a polyphasic approach. In the 16S rRNA gene phylogenetic analysis, strain MKW3 clustered with two misidentified strains-Nostoc sp. CENA239 and Calothrix sp. NIES2100. The phylogenetically related members included strains identified as Nostoc, Aulosira, Calothrix, Tolypothrix, Camptylonemopsis and Microchaete. The phylogenetic and the morphological analysis of the strain MKW3 indicated that it does not belong to any of the above mentioned genera. Furthermore, the 16S-23S ITS secondary structure analysis provided clear evidence indicating that strain MKW3 is different from Nostoc sp. CENA239 and Calothrix sp. NIES2100. Based on the morphological, phylogenetic and 16S-23S ITS secondary structure analysis we describe our strain as Constrictifilum karadense gen. et sp. nov. in accordance with the International Code of Nomenclature for algae, fungi and plants. � 2021 The Author(s). Published by Oxford University Press on behalf of FEMS. All rights reserved.
Description of Cylindrospermum solincola sp. nov. from Jammu and Kashmir, India and Further Insights into the Ecological Distribution and Morphological Attributes of Cylindrospermum badium
(MDPI, 2023) Kumar, Naresh; Saraf, Aniket; Pal, Sagarika; Singh, Prashant
Two cyanobacterial strains KUT1-PS and 18C-PS were collected from the soil surface and vernal pool, respectively, from the Basantgarh village, Udhampur district of the union territory of Jammu and Kashmir, India and characterized by a polyphasic approach. The morphological characterization indicated that both the strains showed typical Cylindrospermum-like morphology and probably belonged to the genus Cylindrospermum. Further, phylogenetic interpretations at the genus level were made using the 16S rRNA gene while the 16S-23S ITS region phylogenetic analysis and secondary structure analysis were conducted to enhance the resolution at the species level. The results from the comparative morphological analysis, the 16S rRNA gene percent similarity and phylogenetic analyses, the 16S-23S ITS percent dissimilarity and the ITS secondary structure analyses provided enough evidence that the strain 18C-PS is a representative of Cylindrospermum badium, providing further insights into its ecological distribution and morphological attributes. Additionally, the strain KUT1-PS was a novel species of the genus Cylindrospermum and is referred to herein as Cylindrospermum solincola sp. nov., in accordance with the International Code of Nomenclature for algae, fungi and plants. This study also discusses the importance of comparing the newly sequenced strains with previously established species before making final taxonomic interpretations. � 2023 by the authors.
Digging deeper into the taxonomy of Cylindrospermum and description of Johanseniella tripurensis gen. et sp. nov. from India
(Oxford University Press, 2022) Pal, Sagarika; Saraf, Aniket; Kumar, Naresh; Singh, Arush; Talukdar, Utkarsh; Kohar, Niraj; Singh, Prashant
The wet soil-inhabiting cyanobacterium URH-6-PS was collected from the state of Tripura, India, and characterized using a polyphasic approach. Initial microscopic analysis indicated the strain to be a member of the genus Cylindrospermum, however, the 16S rRNA gene phylogenetic analysis showed some interesting results. The strain URH-6-PS clustered in the Clade I, which positioned itself outside the Cylindrospermum sensu stricto clade with strong probability/bootstrap support, indicating that the strain may not belong to the genus Cylindrospermum. Further, analysis of the 16S-23S ITS region using the folded secondary structures of the D1-D1?, Box-B, and V3 helices and the 16S-23S ITS percentage dissimilarity values clearly indicated the distinctiveness of strain URH-6-PS from other members of the Clade I. The detailed investigations conducted in this study provided sufficient evidence that the taxonomic status of the members of Clade I need to be revised. Interestingly, all members of the clade I originated from tropical and subtropical habitats while members of the Cylindrospermum sensu stricto clade have been reported from temperate conditions. Previous studies had also indicated the possibility of the formation of tropical and subtropical Cylindrospermum-like genera, and thus this comes across as a much-awaited study to resolve the taxonomic complexities around the genus Cylindrospermum. Based on the results obtained in this study and the trends observed in the earlier studies, we describe a novel Cylindrospermum-like genus Johanseniella gen. nov., with the type species Johanseniellatripurensis sp. nov. in accordance with the International Code of Nomenclature for algae, fungi, and plants. � 2022 The Author(s). Published by Oxford University Press on behalf of FEMS.
Insights into the phylogenetic inconsistencies of the genus Amazonocrinis and description of epilithic Amazonocrinis malviyae sp. nov. (Cyanobacteria, Nostocales) from Jammu and Kashmir, India
(Microbiology Society, 2022) Kumar, Naresh; Saraf, Aniket; Pal, Sagarika; Mishra, Deeksha; Singh, Prashant
A dark-coloured thin film of cyanobacteria growing on the bottom of a submerged stone was isolated from Basantgarh village in Udhampur district, Jammu and Kashmir, India. The isolated strain (designated 19C-PST ) was characterized using a polyphasic approach. The strain exhibited typical Nostoc-like morphology with a characteristic feature of having hetero-cytes in series. The 16S rRNA gene phylogeny placed the strain at a well-supported and distinct node. Notably, the recently described genus, Amazonocrinis, on the addition of more 16S rRNA gene sequences, reflected a critical split, which proved to be stable and well supported in all phylogenetic analyses of the 16S rRNA gene. Interestingly, Amazonocrinis nigriter-rae CENA67T (type species of the genus) clustered together with our strain 19C-PST in the 16S rRNA gene phylogenetic analysis while the rest of the members of the genus Amazonocrinis were placed at a separate and distant node. This clearly indicated that strain 19C-PST is a member of Amazonocrinis sensu stricto. However, the results of phylogenetic analysis of ITS sequences only, in strains purported to belong to Amazonocrinis did not agree with the 16S rRNA gene results and placed our strain 19C-PST in a sister clade to three strains that have not yet been speciated, UHCC 0702, NIES-4103 and SA22, with A. nigriterrae falling into a separate clade. Further, folded secondary structures of the D1�D1?, V2, BoxB and V3 helices of strain 19C-PST were found to be significantly different from those of all the phylogenetically related taxa. The study revealed an interesting case where low taxon sampling and phylogenomic interpretations came across as points of attention in cyanobacterial taxonomy. Based on the morphological, phylogenetic, 16S�23S ITS secondary structure analy-ses, we describe our strain as Amazonocrinis malviyae sp. nov. in accordance with the International Code of Nomenclature for algae, fungi and plants. This work also illuminates the need for further research to resolve the taxonomic discrepancies among Amazonocrinis strains. � 2022 The Authors.
Issues in cyanobacterial taxonomy: Comprehensive case study of unbranched, false branched and true branched heterocytous cyanobacteria
(Oxford University Press, 2021) Mishra, Deeksha; Saraf, Aniket; Kumar, Naresh; Pal, Sagarika; Singh, Prashant
The order Nostocales is represented by morphologically diverse forms with respect to the branching patterns and polarity of the filaments. With growing understanding of taxonomy and systematics, members of the order Nostocales have also undergone multiple taxonomic revisions. The last decade has seen a surge in the description of new genera and families within the order Nostocales. In this study, we discuss the taxonomic status of all the newly described and reclassified taxa of some of the prominent morphological forms within the order Nostocales by constructing comprehensive phylogenetic trees. Further, we propose certain strategies that would contribute to resolving the taxonomic complexities arising due to inadequate taxon sampling. � 2021 The Author(s).
Phycological exploration of the global biodiversity hotspots of Northeast India: discovery of a new species of soil-dwelling cyanobacteria, Desikacharya kailashaharensis sp. nov
(Oxford University Press, 2022) Pal, Sagarika; Saraf, Aniket; Kumar, Naresh; Singh, Prashant
A soil-dwelling cyanobacterial strain (KLS-BP-3A_PS), has been isolated from the biodiversity rich Northeast region of India and characterized using a polyphasic approach. The strain was collected from a field covered with grass, near a stream from the Unakoti district of Tripura. Upon culturing in the laboratory, initial studies indicated the strain to be showing typical Nostoc or Nostoc-like morphology. Subsequently, 16S rRNA gene phylogenetic analyses using Neighbour joining, Maximum-likelihood, and Bayesian inference methods gave a distinct and stable positioning of the strain inside the genus Desikacharya. Upon recovery of the full-length operon of the 16S-23S ITS region with both tRNAs (tRNAIle and tRNAAla), the folded secondary structures revealed unique patterns of the D1-D1', V2, Box-B, and V3 regions of the strain KLS-BP-3A_PS as compared to phylogenetically related species of the genus Desikacharya. The total evidence approach indicated conclusively that the strain under investigation is a new species of the genus Desikacharya, which we describe as Desikacharya kailashaharensis in accordance with the International Code of Nomenclature for algae, fungi, and plants. Further, 16S rRNA gene phylogeny and evaluation of the 16S-23S ITS operons along with implying a re-examination of the family level affiliation of Desikacharya as well its generic limits may be in order. Notably, this study brings into focus the very less explored Northeast region of India which shares two global biodiversity hotspots in the world. � 2022 The Author(s). Published by Oxford University Press on behalf of FEMS.
Polyphasic Approach and Cyanobacterial Taxonomy: Some Perspectives and Case Studies
(Springer Nature, 2022) Saraf, Aniket; Dawda, Himanshu G.; Singh, Prashant
Cyanobacteria are oxygen-producing, photosynthesizing, gram-negative prokaryotes, which played a major role in the development of the atmosphere of the present earth. Despite being so old and omnipresent, it is surprising that proper and correct identification of cyanobacteria is still a challenge and has often created confusing patterns. The primary reason for all this confusion is the morphological plasticity of these organisms, which eventually creates confusion during long-term studies. This fact makes the study of cyanobacteria both challenging and interesting too. The taxonomy of cyanobacteria for a long time was based only on the morphological criterion, which, in the modern times, has raised many questions, which need to be answered by adopting an approach that respects both the classical morphology and the modern methods based on genetic information and phylogeny. The amalgamation of both the classical and the modern methods has led to the development of the polyphasic approach. Unfortunately, at the present moment what all constitutes a polyphasic approach is still under scrutiny, thus making the taxonomy of cyanobacteria complicated and challenging. Modern taxonomists must solve all the abovementioned problems by adopting an approach that reflects in a considerate way the morphology, ecology, and the molecular phylogeny. Unequal, biased preference or convenience-based methods are posing hindrances and thus lead to ambiguities that are tough to resolve. The future of cyanobacterial taxonomy may lie in the proper usage of the polyphasic approach with more revisionary works being anticipated. � The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021.
Roholtiella volcanica sp. nov., a New Species of Cyanobacteria from Kamchatkan Volcanic Soils
(MDPI, 2022) Gaysina, Lira A.; Johansen, Jeffrey R.; Saraf, Aniket; Allaguvatova, Rezeda Z.; Pal, Sagarika; Singh, Prashant
During a study of biodiversity of cyanobacteria in Gorely volcano soils (Kamchatka Peninsula), a strain of heterocytous, a false branching cyanobacterium with gradually tapered filaments, was isolated. Prominent features of the strain were purplish-grey trichomes and firm, distinct multilayered sheaths. Based on the results obtained from the morphological, ecological, and phylogenetic analysis using the 16S rRNA and 16S�23S ITS region, 16S�23S ITS secondary structure analysis, comparison of flanking regions of BoxB and V3 helices, and the p-distance between the 16S�23S ITS region, we describe our strain K7 as a novel species of the genus Roholtiella with the name Roholtiella volcanica sp. nov., in accordance with the International Code of Nomenclature for algae, fungi, and plants. This work continues the rapid expansion of the description of new taxa of cyanobacteria, and particularly demonstrates a coming phase in cyanobacterial taxonomy in which the discovery of new species in recently described genera rapidly increases our understanding of the diversity in this phylum. � 2022 by the authors.

Browsing by Author "Saraf, Aniket"

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