Nocardiopsis mwathae sp. nov., isolated from the haloalkaline Lake Elmenteita in the African Rift Valley.

During a screening for novel and biotechnologically useful bacteria in haloalkaline lakes, strain No.156(T) was isolated from a sediment sample from lake Elmenteita in the African Rift Valley and studied by a polyphasic taxonomic approach. The strain was observed to form yellow aerial and substrate mycelia; optimal growth was found to be at 30-35 °C in salt concentrations of 6-9 % (w/v) and at pH 7-9. The DNA G+C content of the novel strain was 71 mol%. Analysis of 16S rRNA sequences indicated that the isolate belongs to the genus Nocardiopsis with sequence similarities below 98 % to the type strains of all other representatives of the genus. Mycolic acids were not detected in whole cell methanolysates. The peptidoglycan was found to contain meso-diaminopimelic acid as the diamino acid with no diagnostic sugars. The main polar lipids were identified as phosphatidylmethylethanolamine, phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol but no diphosphatidylglycerol. The predominant menaquinones were MK-11(H8), MK-11(H6), MK-10(H8) and MK-10(H6). Cellular fatty acids were found to consist of saturated and monounsaturated iso- and anteiso-branched acids with 16-18 C-length, tuberculostearic acid (Me18:0), and straight-chain saturated (16:0, 18:0) acids. These characteristics match those of the genus Nocardiopsis. Based on 16S rRNA gene sequence analysis and phenotypic characteristics, a novel species with the name Nocardiopsis mwathae is proposed. The type strain is No.156(T) (=DSM 46659(T) = CECT 8552(T)). The INSDC accession number for the 16S rRNA gene sequence of strain No.156(T) is KF976731

Belliella kenyensis sp. nov., isolated from an alkaline lake.

A red-pigmented, Gram-reaction-negative, aerobic bacterial strain, designated No.164(T), was isolated from sediment sample from the alkaline Lake Elmenteita located in the Kenyan Rift Valley. Results of 16S rRNA gene sequence analysis indicated that the isolate represented a member of the genus Belliella, with the highest sequence similarity (97 %) to Belliella pelovolcani DSM 46698(T). Optimal growth temperature was 30-35 °C, at pH 7.0-12.0 in the presence of 0-4 % (w/v) NaCl. Flexirubins were absent. The respiratory menaquinone (MK-7), predominant cellular fatty acids (iso-C15 : 0, anteiso-C15 : 0 and a mixture of C16 : 1ω7c and/or iso-C15 : 0 2-OH) and DNA G+C content (38.1 mol%) of strain No.164(T) were consistent with those of other members of the genus Belliella. The polar lipids consisted of phosphatidylethanolamine, eight unspecified lipids and one unspecified phospholipid. Several phenotypic characteristics can be used to differentiate this isolate from those of other species of the genus Belliella. The results of polyphasic analyses presented in this study indicated that this isolate should be classified as representing a novel species of the genus Belliella. The name Belliella kenyensis sp. nov. is therefore proposed; the type strain is strain No.164(T) ( = DSM 46651(T) = CECT 8551(T))

Comparative genomic analysis of eight novel haloalkaliphilic bacteriophages from Lake Elmenteita, Kenya.

We report complete genome sequences of eight bacteriophages isolated from Haloalkaline Lake Elmenteita found on the floor of Kenyan Rift Valley. The bacteriophages were sequenced, annotated and a comparative genomic analysis using various Bioinformatics tools carried out to determine relatedness of the bacteriophages to each other, and to those in public databases. Basic genome properties like genome size, percentage coding density, number of open reading frames, percentage GC content and gene organizations revealed the bacteriophages had no relationship to each other. Comparison to other nucleotide sequences in GenBank database showed no significant similarities hence novel. At the amino acid level, phages of our study revealed mosaicism to genes with conserved domains to already described phages. Phylogenetic analyses of large terminase gene responsible for DNA packaging and DNA polymerase gene for replication further showed diversity among the bacteriophages. Our results give insight into diversity of bacteriophages in Lake Elmenteita and provide information on their evolution. By providing primary sequence information, this study not only provides novel sequences for biotechnological exploitation, but also sets stage for future studies aimed at better understanding of virus diversity and genomes from haloalkaline lakes in the Rift Valley

Isolation, characterization and analysis of bacteriophages from the haloalkaline lake Elmenteita, Kenya.

As a step towards better understanding of diversity and biology of phages and their hosts in haloalkaline Lake Elmenteita, phages were isolated from sediment samples and overlying water using indigenous bacteria as hosts. 17 seemingly different phages of diverse morphotypes with different dimensions and partly exhibiting remarkably unusual ultrastructures were revealed by transmission electron microscopy. 12 clonal phage isolates were further characterized. Infection capability of the phages was optimum at 30–35°C and in alkali condition with optimum at pH 10–12. Structural protein profiles and restriction fragment length polymorphism analyses patterns were distinct for each of the phage type. Complete nucleotide sequences of phages vB-VmeM-32, vB_EauS-123 and vB_BhaS-171 genomes varied in size from 30,926–199,912 bp and G + C content of between 36.25–47.73%. A range of 56–260 potential open reading frames were identified and annotated. The results showed that the 12 phages were distinct from each other and confirmed the presence and diversity of phages in extreme environment of haloalkaline Lake Elmenteita. The phages were deposited at the German Collection of Microorganisms and Cell Cultures and three of their genomes uploaded to NCBI GenBank.As a step towards better understanding of diversity and biology of phages and their hosts in haloalkaline Lake Elmenteita, phages were isolated from sediment samples and overlying water using indigenous bacteria as hosts. 17 seemingly different phages of diverse morphotypes with different dimensions and partly exhibiting remarkably unusual ultrastructures were revealed by transmission electron microscopy. 12 clonal phage isolates were further characterized. Infection capability of the phages was optimum at 30-35°C and in alkali condition with optimum at pH 10-12. Structural protein profiles and restriction fragment length polymorphism analyses patterns were distinct for each of the phage type. Complete nucleotide sequences of phages vB-VmeM-32, vB_EauS-123 and vB_BhaS-171 genomes varied in size from 30,926-199,912 bp and G + C content of between 36.25-47.73%. A range of 56-260 potential open reading frames were identified and annotated. The results showed that the 12 phages were distinct from each other and confirmed the presence and diversity of phages in extreme environment of haloalkaline Lake Elmenteita. The phages were deposited at the German Collection of Microorganisms and Cell Cultures and three of their genomes uploaded to NCBI GenBank