| alkalimonas amylolytica gen. nov., sp. nov., and alkalimonas delamerensis gen. nov., sp. nov., novel alkaliphilic bacteria from soda lakes in china and east africa. | two related novel alkaliphilic and slightly halophilic bacteria are described. they are strain n10 from lake chahannor in china and strain 1e1 from lake elmenteita in east africa. both strains are strictly aerobic, heterotrophic, alkaliphilic, mesophilic, and require nacl for growth. the optimal conditions for growth were at ph 10-10.5 and 2-3% (w/v) nacl. cells of both strains were gram-negative, rod-shaped, non-spore-forming, and motile with a single polar flagellum. cellular fatty acids in bo ... | 2004 | 14986177 |
| the activity profile of the nhad-type na+(li+)/h+ antiporter from the soda lake haloalkaliphile alkalimonas amylolytica is adaptive for the extreme environment. | in extreme alkaliphiles, na(+)/h(+) antiporters play a central role in the na(+) cycle that supports ph homeostasis, na(+) resistance, solute uptake, and motility. properties of individual antiporters have only been examined in extremely alkaliphilic soil bacillus spp., whereas the most alkaline natural habitats usually couple high ph with high salinity. here, studies were conducted on a na(+)(li(+))/h(+) antiporter, nhad, from the soda lake haloalkaliphile alkalimonas amylolytica. the activity ... | 2005 | 16267283 |
| [study on the membrane proteins of alkalimonas amylolytica n10 expressed at different ph environment]. | the research on the membrane proteins expressed in alkaliphiles at different ph media will be benefit to understand the molecular mechanisms how they survive from such harsh alkaline environment. a preliminary investigation to the differential membrane proteomes from alkalimonas amylolytica n10 (n10), a novel alkaliphilic bacterium, is reported herein. upon the growth curves of n10 at different ph environment, three ph media, 8.4, 9.4 and 10.4, respectively, were employed to culture n10 followed ... | 2006 | 16736589 |
| nhad type sodium/proton-antiporter of halomonas elongata: a salt stress response mechanism in marine habitats? | sodium/proton-antiporters (nha) are known to play an important role in ph- and na+-homeostasis. in microorganisms several types with different capacity, affinity and selectivity for na+ and li+ exist. the homeostasis system of e. coli, nhaa and nhab, is well researched, but the function of other types of na+/h+-antiporters like nhad is yet to be fully understood. since several antiporters play an important role at various points in the physiology of higher organisms, one can speculate that the m ... | 2006 | 16872527 |
| gene cloning and characterization of a novel alpha-amylase from alkaliphilic alkalimonas amylolytica. | a gene encoding an extracellular alpha-amylase (amya) was cloned from the alkaliphilic bacterium alkalimonas amylolytica by enzymatic activity screening in escherichia coli dh5alpha. the gene amya consists of 1764 base pairs and was predicted to encode a 587-amino acid protein encompassing a 31-amino acid signal peptide. in addition, a 459-amino acid catalytic domain and a 97-amino acid starch-binding domain (sbd) were found. the sbd showed little similarity to other known sbds; instead, it cont ... | 2006 | 17068753 |
| three putative cation/proton antiporters from the soda lake alkaliphile alkalimonas amylolytica n10 complement an alkali-sensitive escherichia coli mutant. | attempts to identify members of the antiporter complement of the alkali- and saline-adapted soda lake alkaliphile alkalimonas amylolytica n10 have used screens of dna libraries in antiporter-deficient escherichia coli knabc. earlier screens used na(+) or li(+) for selection but only identified one nhad-type antiporter whose properties were inconsistent with a robust role in ph homeostasis. here, new screens using elevated ph for selection identified three other putative antiporter genes that con ... | 2007 | 17600061 |
| alkalimonas collagenimarina sp. nov., a psychrotolerant, obligate alkaliphile isolated from deep-sea sediment. | a psychrotolerant, obligately alkaliphilic, collagenolytic enzyme-producing bacterium, strain ac40(t), was isolated from a deep-sea sediment off torishima island, japan, at a depth of 4026 m. phylogenetic analysis of 16s rrna gene sequences indicated that this bacterium was closely related to members of the genus alkalimonas, with highest sequence similarity (97.9 %) to alkalimonas delamerensis 1e1(t). dna-dna hybridization experiments of strain ac40(t) with a. delamerensis 1e1(t) revealed a lev ... | 2007 | 17625192 |
| nucleotide and deduced amino acid sequences of a subtilisin-like serine protease from a deep-sea bacterium, alkalimonas collagenimarina ac40(t). | the acpi gene encoding an alkaline protease (acpi) from a deep-sea bacterium, alkalimonas collagenimarina ac40(t), was shotgun-cloned and sequenced. it had a 1,617-bp open reading frame encoding a protein of 538 amino acids. based on analysis of the deduced amino acid sequence, acpi is a subtilisin-like serine protease belonging to subtilase family a. it consists of a prepropeptide, a catalytic domain, and a prepeptidase c-terminal domain like other serine proteases from the genera pseudomonas, ... | 2007 | 17786425 |
| exploring membrane and cytoplasm proteomic responses of alkalimonas amylolytica n10 to different external phs with combination strategy of de novo peptide sequencing. | identification of differentially proteomic responses to external phs would pave an access for understanding of survival mechanisms of bacteria living at extreme ph environment. we cultured alkalimonas amylolytica n10 (n10), a novel alkaliphilic bacterium found in lake chahannor, in media with three different phs and extracted the correspondent membrane and cytoplasm proteins for proteomic analysis through 2-de. the differential 2-de spots corresponding to the altered phs were delivered to maldi ... | 2009 | 19253282 |
| collagenolytic subtilisin-like protease from the deep-sea bacterium alkalimonas collagenimarina ac40t. | a new alkaline protease (acpii) was purified from a culture of the deep-sea bacterium alkalimonas collagenimarina ac40(t). acpii degraded collagen three times faster than it degraded casein. the optimal ph was 8.5-9, and the optimal temperature was 45 degrees c for the degradation of collagen. acpii was completely inhibited by phenylmethylsulfonyl fluoride and partially by edta. cloning and sequencing the gene for acpii revealed a 2,283-bp open reading frame encoding a protein of 760 amino acids ... | 2010 | 19888572 |
| characterization and function analysis of a halo-alkaline-adaptable trk k+ uptake system in alkalimonas amylolytica strain n10. | by functional complementation of escherichia coli mutants defective in potassium (k(+)) uptake, two genes that are required for k(+) uptake in halo-alkaliphilic alkalimonas amylolytica strain n10 were cloned. these two genes, aa-trka (1337 bp) and aa-trkh (1452 bp), were adjacent on the a. amylolytica n10 chromosome and transcribed in opposite directions. complementation experiments revealed that aa-trka and aa-trkh from a. amylolytica strain n10 restored the ability to grow at low k(+) concentr ... | 2009 | 19911131 |
| isolation and characterisation of bacteria from the haloalkaline lake elmenteita, kenya. | culture-independent studies show that soda lake environments harbour diverse groups of bacteria and archaea. in this study different enrichment and isolation media were used in an attempt to isolate novel groups of bacteria from lake elmenteita. different media were prepared using filter-sterilised water from the lake. the isolates recovered were purified on tryptic soy agar supplemented with 1% sodium carbonate and 4% sodium chloride. phylogenetic analysis of 181 partial 16s rrna gene sequences ... | 2010 | 20401502 |
| metagenome cloning and functional analysis of na(+)/h (+) antiporter genes from keke salt lake in china. | na(+)/h(+) antiporters are ubiquitous membrane proteins and play a central role in cell homeostasis including ph regulation, osmoregulation, and na(+)/li(+) tolerance in bacteria. the microbial communities in extremely hypersaline soil are an important resource for isolating na(+)/h(+) antiporter genes. a metagenomic library containing 35,700 clones was constructed by using genomic dna obtained from the hypersaline soil samples of keke salt lake in northwest of china. two na(+)/h(+) antiporters, ... | 2011 | 22101456 |