Evidence for Autotrophy via the Reverse Tricarboxylic Acid Cycle in the Marine Magnetotactic Coccus Strain MC-1

Strain MC-1 is a marine, microaerophilic, magnetite-producing, magnetotactic coccus phylogenetically affiliated with the α-Proteobacteria. Strain MC-1 grew chemolithotrophically with sulfide and thiosulfate as electron donors with HCO₃⁻/CO₂ as the sole carbon source. Experiments with cells grown microaerobically in liquid with thiosulfate and H¹⁴CO₃⁻/¹⁴CO₂ showed that all cell carbon was derived from H¹⁴CO₃⁻/¹⁴CO₂ and therefore that MC-1 is capable of chemolithoautotrophy. Cell extracts did not exhibit ribulose-1,5-bisphosphate carboxylase-oxygenase (RubisCO) activity, nor were RubisCO genes found in the draft genome of MC-1. Thus, unlike other chemolithoautotrophic, magnetotactic bacteria, strain MC-1 does not appear to utilize the Calvin-Benson-Bassham cycle for autotrophy. Cell extracts did not exhibit carbon monoxide dehydrogenase activity, indicating that the acetyl-coenzyme A pathway also does not function in strain MC-1. The ¹³C content of whole cells of MC-1 relative to the ¹³C content of the inorganic carbon source (Δδ¹³C) was −11.4 . Cellular fatty acids showed enrichment of ¹³C relative to whole cells. Strain MC-1 cell extracts showed activities for several key enzymes of the reverse (reductive) tricarboxylic acid (rTCA) cycle including fumarate reductase, pyruvate:acceptor oxidoreductase and 2-oxoglutarate:acceptor oxidoreductase. Although ATP citrate lyase (another key enzyme of the rTCA cycle) activity was not detected in strain MC-1 using commonly used assays, cell extracts did cleave citrate, and the reaction was dependent upon the presence of ATP and coenzyme A. Thus, we infer the presence of an ATP-dependent citrate-cleaving mechanism. These results are consistent with the operation of the rTCA cycle in MC-1. Strain MC-1 appears to be the first known representative of the α-Proteobacteria to use the rTCA cycle for autotrophy.     

Complete Genome Sequence of the Marine, Chemolithoautotrophic, Ammonia-Oxidizing Bacterium Nitrosococcus oceani ATCC 19707

The gammaproteobacterium Nitrosococcus oceani (ATCC 19707) is a gram-negative obligate chemolithoautotroph capable of extracting energy and reducing power from the oxidation of ammonia to nitrite. Sequencing and annotation of the genome revealed a single circular chromosome (3,481,691 bp; G+C content of 50.4%) and a plasmid (40,420 bp) that contain 3,052 and 41 candidate protein-encoding genes, respectively. The genes encoding proteins necessary for the function of known modes of lithotrophy and autotrophy were identified. Contrary to betaproteobacterial nitrifier genomes, the N. oceani genome contained two complete rrn operons. In contrast, only one copy of the genes needed to synthesize functional ammonia monooxygenase and hydroxylamine oxidoreductase, as well as the proteins that relay the extracted electrons to a terminal electron acceptor, were identified. The N. oceani genome contained genes for 13 complete two-component systems. The genome also contained all the genes needed to reconstruct complete central pathways, the tricarboxylic acid cycle, and the Embden-Meyerhof-Parnass and pentose phosphate pathways. The N. oceani genome contains the genes required to store and utilize energy from glycogen inclusion bodies and sucrose. Polyphosphate and pyrophosphate appear to be integrated in this bacterium's energy metabolism, stress tolerance, and ability to assimilate carbon via gluconeogenesis. One set of genes for type I ribulose-1,5-bisphosphate carboxylase/oxygenase was identified, while genes necessary for methanotrophy and for carboxysome formation were not identified. The N. oceani genome contains two copies each of the genes or operons necessary to assemble functional complexes I and IV as well as ATP synthase (one H⁺-dependent F₀F₁ type, one Na⁺-dependent V type).     

Complete Genome Sequence of Mycoplasma hyorhinis Strain HUB-1

Mycoplasma hyorhinis is generally considered a swine pathogen yet is most commonly found infecting laboratory cell lines. An increasing body of evidence suggests that chronic infections with M. hyorhinis may cause oncogenic transformation. Here, we announce the complete genome sequence of M. hyorhinis strain HUB-1.Mycoplasma hyorhinis is generally considered to be a swine pathogen causing lung lesions, inflammation in the chest and abdominal lining, and arthritis (8). This agent also frequently contaminates laboratory cell cultures, impinging on many aspects of biological research (3). Recent studies have demonstrated that M. hyorhinis infections induce a malignant phenotype in human prostate (7) and gastric (4) cells, suggesting that M. hyorhinis infections are associated with oncogenic transformation. These properties of M. hyorhinis have increased its profile to researchers. The complete genome sequence of this microbe has yet to be determined.We sequenced the genome of M. hyorhinis strain HUB-1, a pathogenic strain isolated from the respiratory tract of swine. Whole-genome sequencing was performed by combining GS FLX (6) and Solexa paired-end sequencing technologies (1). Genomic libraries containing 3-kb inserts were constructed, and 308,604 reads (79.7% paired end) were produced using the GS FLX system, giving 65.9-fold coverage of the genome. About 93.4% of reads were assembled into one large scaffold using Newbler software (454 Life Sciences, Branford, CT). A total of 822,579 reads were generated using an Illumina Solexa Genome Analyzer IIx and were mapped to the scaffold using the Burrows-Wheeler alignment (BWA) tool (5). Gaps were filled by local assembly of the Solexa/Roche 454 reads or by sequencing PCR products by using an ABI 3730 capillary sequencer. Open reading frames containing more than 30 amino acid residues were predicted using Glimmer 3.0 (2) and verified by comparison with six other closely related genome sequences.The complete genome of M. hyorhinis HUB-1 consists of an 839,615-bp single circular chromosome with an average G+C content of 25.88%. A total of 654 protein-encoding genes are predicted. The average protein size is 364 amino acids, and the mean coding percentage is 85.2%. The genome includes 30 tRNA genes, and only a single copy of the 16S-23S rRNA operon can be found. The 5S rRNA operon is separate from the 16S-23S rRNA operon. Protein secretion occurs through a truncated membrane protein secretion system, consisting of SecA, SecD, SecY, PrsA, DnaK, Tig, and LepA. Additionally, 20 pseudogenes, which become truncated or inactivated, are identified in the genome.M. hyorhinis contains a special variable lipoprotein (Vlp) system that constitutes its major coat protein (9) and provides a mutational strategy for evasion of the host immune system. Different M. hyorhinis strains carry a variable number of vlp genes (9). M. hyorhinis HUB-1 is characterized to contain seven vlp genes displayed in the order 5′-vlpD-vlpE-vlpF-insertion sequence (IS)-vlpG-vlpA-IS-vlpB-vlpC-3′.This is the first complete genome sequence of M. hyorhinis, and its availability will provide a better-defined genetic background for future studies of gene expression and regulation.     

Complete Genome Sequence of the Facultative Anaerobic Magnetotactic Bacterium Magnetospirillum sp. strain AMB-1

Magnetospirillum sp. strain AMB-1 is a Gram-negative -proteobacteriumthat synthesizes nano-sized magnetites, referred to as magnetosomes,aligned intracellularly in a chain. The potential of this nano-sizedmaterial is growing and will be applicable to broad researchareas. It has been expected that genome analysis would elucidatethe mechanism of magnetosome formation by magnetic bacteria.Here we describe the genome of Magnetospirillum sp. AMB-1 wildtype, which consists of a single circular chromosome of 4967148bp. For identification of genes required for magnetosome formation,transposon mutagenesis and determination of magnetosome membraneproteins were performed. Analysis of a non-magnetic transposonmutant library focused on three unknown genes from 2752 unknowngenes and three genes from 205 signal transduction genes. Partialproteome analysis of the magnetosome membrane revealed thatthe membrane contains numerous oxidation/reduction proteinsand a signal response regulator that may function in magnetotaxis.Thus, oxidation/reduction proteins and elaborate multidomainsignaling proteins were analyzed. This comprehensive genomeanalysis will enable resolution of the mechanisms of magnetosomeformation and provide a template to determine how magnetic bacteriamaintain a species-specific, nano-sized, magnetic single domainand paramagnetic morphology.     

Complete Genome Sequence of the Copiotrophic Marine Bacterium Alteromonas macleodii Strain ATCC 27126T

The genome of Alteromonas macleodii strain ATCC 27126^T has been resequenced and closed into a single contig. We describe here the genome of this important and globally distributed marine bacterium.     

Complete Genome Sequence of the Diesel-Degrading Acinetobacter sp. Strain DR1

The genus Acinetobacter is ubiquitous in soil, aquatic, and sediment environments and includes pathogenic strains, such as A. baumannii. Many Acinetobacter species isolated from various environments have biotechnological potential since they are capable of degrading a variety of pollutants. Acinetobacter sp. strain DR1 has been identified as a diesel degrader. Here we report the complete genome sequence of Acinetobacter sp. DR1 isolated from the soil of a rice paddy.The genus Acinetobacter appears to be metabolically versatile and has the ability to degrade aliphatic hydrocarbon, thus making it an organism of interest for its possible bioremediational potential (9). Despite its biotechnological potential, the majority of genome projects conducted with Acinetobacter species have focused on pathogenic strains of A. baumannii. Currently, the only available whole-genome sequence of environmental isolates is that of A. baylyi ADP1 (2). Acinetobacter sp. strain DR1 was isolated from the soil of rice paddies, located in Deok-So (Korea University Agricultural Station), in the Kyonggi province of South Korea. Strain DR1 is capable of utilizing aliphatic hydrocarbons and diesel oil (5). Similarly to A. baylyi ADP1, this strain is also competent for natural transformation. We demonstrated previously that sodium chloride added to the medium induces the overproduction of exopolysaccharide (EPS), which evidences protective activity against diesel toxicity (4). Interestingly, DR1 possesses a quorum sensing (QS) system, which has been shown to play a significant role in biofilm formation and hexadecane biodegradation. The results of proteomic studies have demonstrated that the QS system regulates a broad variety of proteins (6). Collectively, our findings demonstrate that DR1 has profound potential for environmental applications and is an environmental isolate distinct from pathogenic strains, thus indicating that the whole-genome sequencing of DR1 is a worthwhile pursuit.Initial pyrosequencing using a GS-FLX system (454 Life Science Corporation) generated 652,162 reads (264,482,836 nucleotides; 64.3-fold coverage), which were assembled into 56 contigs. To determine the order of the contigs, 1,248 fosmid clones were constructed with an average insert size of 35 kb (10.5-fold coverage). The fosmid-end sequencing of 936 clones generated 1,372,452 bp. These high-quality Sanger reads allowed the assembly of 41 large contigs into 2 scaffolds containing 38 gaps. The gaps were filled via primer walking. All procedures for genome sequencing and gap filling were conducted by Macrogen (Seoul, South Korea). Protein coding regions were predicted with the GLIMMER3 software program (3), and automatic genome annotation was conducted on a RAST server (1) and the NCBI Prokaryotic Genomes Automatic Annotation Pipeline (PGAAP). The tRNA and rRNA genes were annotated using the tRNAScan-SE (8) and RNAmmer software programs (7), respectively. The genome of Acinetobacter sp. DR1 consists of a circular 4,152,543-bp chromosome with a G+C content of 38%, 3,874 predicted coding sequences, and 71 tRNAs. There are 6 rRNA operons with a 16S, tRNA-Ile, tRNA-Ala, 23S, 5S organization. The genes studied previously were clearly identified via genome sequencing (4, 5, 6). The availability of the complete genome sequence of Acinetobacter sp. strain DR1 will contribute to an in-depth understanding of the genetic potentials of Acinetobacter species.     

Complete Genome Sequence of Porcine Circovirus 2b Strain CC1

A porcine circovirus 2 (PCV2) strain, designated CC1, was isolated and purified from tissue samples from pigs with wasting syndromes in China. We report the complete genome sequence of PCV2b strain CC1 with a deletion of C at position 1053 resulting in elongation of open reading frame 2 (ORF2) and formation of ORF5. There were 11 ORFs in the genome.     

Complete Genome Sequence of Mycoplasma wenyonii Strain Massachusetts

Mycoplasma wenyonii is a hemotrophic mycoplasma that causes acute and chronic infections in cattle. Here, we announce the first complete genome sequence of this organism. The genome is a single circular chromosome with 650,228 bp and G+C% of 33.9. Analyses of M. wenyonii genome will provide insights into its biology.     

Complete Genome Sequence of the Pyrene-Degrading Bacterium Cycloclasticus sp. Strain P1

Cycloclasticus sp. strain P1 was isolated from deep-sea sediments of the Pacific Ocean and characterized as a unique bacterium in the degradation of pyrene, a four-ring polycyclic aromatic hydrocarbon (PAH). Here we report the complete genome of P1 and genes associated with PAH degradation.     

Complete Genome Sequence of Streptococcus thermophilus Strain MN-ZLW-002

Streptococcus thermophilus MN-ZLW-002 was originally isolated from traditionally fermented Chinese dairy products. One of the strain-dependent characteristics of this bacterium is its ability to produce exopolysaccharides (EPSs). This study determined and analyzed the genome sequence of MN-ZLW-002. Its complete genome comprised 2,046 genes and 1,848,520 nucleotides with an average GC content of 39%. The EPS cluster of MN-ZLW-002 includes 25 open reading frames (ORFs), and some results indicate a horizontal gene transfer between MN-ZLW-002 and other lactic acid bacteria (LAB).     

Complete Genome Sequence of the Extremophilic Bacillus cereus Strain Q1 with Industrial Applications

Bacillus cereus strain Q1 was isolated from a deep-subsurface oil reservoir in the Daqing oil field in northeastern China. This strain is able to produce biosurfactants and to survive in extreme environments. Here we report the finished and annotated genome sequence of this organism.Bacillus cereus strain Q1 was isolated from a deep-subsurface oil reservoir in the Daqing oil field in northeastern China. This strain can facilitate oil recovery when added to an oil reservoir. This attribute may be partially due to its ability to produce biosurfactants, which assist microbial enhanced oil recovery by lowering interfacial tension at the oil-rock interface (data not shown).The complete genome sequence of B. cereus Q1 was determined by the whole-genome shotgun strategy. Draft assemblies were based on 55,790 high-quality reads. All libraries provided sixfold coverage of the genome. Gap closure was accomplished by primer walking on gap-spanning clones and direct sequencing of combinatorial PCR products. Open reading frame (ORF) predictions were obtained and annotation was performed as described previously (4). GenomeComp was used for genomic comparison with default parameters (5).The genome of B. cereus Q1 is composed of one circular chromosome of 5,214,195 bp and two circular plasmids (pBc239 [239,246 bp] and pBc53 [52,766 bp]) with mean G+C contents of 35.6, 33.5, and 35.1%, respectively. There are 5,657 predicted ORFs, 13 rRNA operons, and 94 tRNA genes for all 20 amino acids, covering 86% of the genome. Putative functions were assigned to 3,946 ORFs. Of the remainder, 1,561 showed similarity to hypothetical proteins and 140 had no detectable homologs in the public protein database (E value, <10⁻¹⁰). Twelve phage-related genes were identified, but no complete prophages were found. Whole-genome comparison showed that Q1 has extensive similarity to the genomes of other members of the B. cereus group and the greatest similarity to nonpathogenic strain B. cereus ATCC 10987 (5,224,283 bp).Genome analysis revealed that B. cereus Q1 contains several genes related to niche-specific adaptations. As a thermophilic bacterium, Q1 can easily adapt to geothermal oil reservoirs. Three thermophily-associated genes (BC1015, BC1017, and BC1018) found in Q1 have orthologs in Moorella thermoacetica ATCC 39073. The latter genes encode the structural maintenance of chromosome protein, exonuclease SbcC, and subunit A of DNA topoisomerase VI, respectively. The presence of the genes involved in the utilization of l-fucose (BC2995 to BC3006) and d-mannose (BC5091 to BC5094, BC5097 to BC5102, and BC5105 to BC5111) helps Q1 use these carbohydrates as carbon sources under glucose-limited conditions. Q1 also contains the nitrate utilization gene cluster (BC2100 to BC2123), including a typical narGHJI operon that encodes membrane-bound nitrate reductase. The nitrate utilization gene cluster might play an important role in helping the strain use nitrate as a nitrogen source and survive under anaerobic or oxygen-limited conditions. Moreover, we found an operon that encodes proteins responsible for producing a novel type of lantibiotic (2), which we designated cereicidin. All of the above-mentioned genes were not found in the other B. cereus group bacteria.One of the notable features of Q1 is its ability to produce biosurfactants. The dhb operon (dhbACEBF), which is involved in nonribosomal peptide synthesis and encodes the biosynthetic template for the catecholic siderophore in B. subtilis (1), was identified in Q1. Downstream of the operon, the sfp gene, which encodes phosphopantetheinyl transferase and is required for production of the lipopeptide antibiotic surfactin in B. subtilis (3), was found. No surfactin synthetase gene (srfAA, srfAB, or srfAC) was found, but the mbtH gene involved in mycobactin synthesis and a gene (BC2300) with an unknown function were found in the region between the dhb operon and the sfp gene. We therefore speculated that these three genes located downstream of the dhbF gene might belong to the dhb operon, which is involved in antibiotic-siderophore-surfactin biosynthesis.The B. cereus Q1 genome provides an excellent platform for the further improvement of this organism for biosurfactant production and extends our understanding of the evolutionary relationships among B. cereus group organisms.     

Complete Genome Sequence of the Naphthalene-Degrading Pseudomonas putida Strain ND6

Pseudomonas putida strain ND6 is an efficient naphthalene-degrading bacterium. The complete genome of strain ND6 was sequenced and annotated. The genes encoding the enzymes involved in catechol degradation by the ortho-cleavage pathway were found in the chromosomal sequence, which indicated that strain ND6 is able to metabolize naphthalene by the catechol meta- and ortho-cleavage pathways.     

Complete Genome Sequence of Alcanivorax dieselolei Type Strain B5

Alcanivorax dieselolei B5^T was isolated from oil-contaminated surface water of the Bohai Sea of China and characterized by the efficient degradation of alkane (C₅-C₃₆). Here we report the complete genome of B5^T and genes associated with alkane degradation.     

Complete Genome Sequence of Porcine Circovirus 2d Strain GDYX

Porcine circovirus type 2 (PCV2) is the etiologic agent of porcine circovirus-associated disease, and it is mainly divided into five genotypes. Here, we report the complete genome sequence of PCV2 strain GDYX, which belongs to PCV2d and has a unique amino acid variation at position 169 (S to G).     

Complete Genome Sequence of Mycobacterium vaccae Type Strain ATCC 25954

Mycobacterium vaccae is a rapidly growing, nontuberculous Mycobacterium species that is generally not considered a human pathogen and is of major pharmaceutical interest as an immunotherapeutic agent. We report here the annotated genome sequence of the M. vaccae type strain, ATCC 25954.     

Complete Genome Sequence of the Broad-Host-Range Strain Sinorhizobium fredii USDA257

Here we announce the complete genome sequence of the symbiotic and nitrogen-fixing bacterium Sinorhizobium fredii USDA257. The genome shares a high degree of sequence similarity with the closely related broad-host-range strains S. fredii NGR234 and HH103. Most strikingly, the USDA257 genome encodes a wealth of secretory systems.     

Complete Genome Sequence of Bacillus thuringiensis Mutant Strain BMB171

Bacillus thuringiensis has been widely used as a biopesticide for a long time. Here we report the finished and annotated genome sequence of B. thuringiensis mutant strain BMB171, an acrystalliferous mutant strain with a high transformation frequency obtained and stocked in our laboratory.Bacillus thuringiensis is an insect pathogen which is widely used as a biopesticide due to its various endogenous crystal proteins and spores (12). To improve the virulence and practical effectiveness of B. thuringiensis, genetic transformation of different genes with beneficial traits is a fundamental procedure. Simultaneously, genetic transformation can facilitate functional genomic research. However, wild-type strains are not suitable to be used as recipient strains because of low transformation efficiency. This obstacle is mainly caused by the thick cell wall layer of B. thuringiensis together with multiple plasmids inside the cell, which harbor genes encoding insecticidal crystal proteins. We used the method of elevating the growth temperature and adding 0.05% sodium dodecyl sulfate to treat several parental strains and finally obtained mutant strain BMB171, with no resident plasmid, from wild-type crystalliferous strain YBT-1463 (9). The electrotransformation frequency of mutant BMB171 could reach up to 10⁷ transformants/μg DNA after optimization of the electrotransformation parameters (7), which was 4.8 × 10⁴-fold higher than that of the parental strain (8). Moreover, mutant strain BMB171 exhibited the same characteristics as YBT-1463, such as metabolic abilities and growth properties, as well as sensitivity to 10 antibiotics (8). Of course, BMB171 could produce parasporal crystals with characteristic geometric shapes through the expression of relevant cry genes carried by plasmids (7). Thus, B. thuringiensis mutant strain BMB171 has become a major recipient strain and is widely used for insecticidal crystal protein-encoding gene expression (14, 15), cell surface display (10, 13), gene function and regulation researches (2, 5), etc.The B. thuringiensis mutant strain BMB171 genome was sequenced by using a massive parallel pyrosequencing technology (454 GS-FLX). A total of 448,963 high-quality reads with an average read length of 391 bp were produced, providing about 32-fold coverage of the genome. Assembly was performed using the Newbler software of the 454 suite package (454 Life Sciences), which resulted in 193 large (defined as >500 bp) contigs. The relationship of contigs was determined by multiplex PCR, and gaps were filled through sequencing of PCR products by primer walking or shotgun sequencing with an ABI 3730 sequencer. The Phred/Phrap/Consed software package (3) was used for final sequence assembly and quality assessment. Protein-coding genes were predicted by combining the results of Glimmer 3.02 (1) and ZCURVE (4), followed by manual inspection. Both tRNA and rRNA genes were identified by tRNAscan-SE (11) and RNAmmer (6), respectively. Functional annotation was performed by searching against a protein database of the microbial genome developed in house.The 5.64-Mb genome of B. thuringiensis mutant strain BMB171 contains two replicons: a circular chromosome (5.33 Mb) encoding 5,088 open reading frames (ORFs) and a circular plasmid (0.31 Mb), which is named pBMB171, encoding 276 predicted ORFs. The G+C content of the chromosome is 35.3%, while that of the plasmid is 33.3%. The mutant strain BMB171 genome encodes 104 tRNAs and 14 rRNA operons. A previous study indicated that BMB171 is a plasmid-free mutant (9); however, our sequencing results demonstrated that a large plasmid still remains. The reason why the plasmid was not detected previously might be its large size and low copy number. We did not find any crystal protein genes in either chromosome or plasmid sequences, which was consistent with previous observations (9).In summary, the complete B. thuringiensis mutant strain BMB171 genome provides a better-defined genetic background for gene expression and regulation studies, especially crystal protein production and metabolic network construction.     

Complete Genome Sequence of the Plant Pathogen Erwinia amylovora Strain ATCC 49946

Erwinia amylovora causes the economically important disease fire blight that affects rosaceous plants, especially pear and apple. Here we report the complete genome sequence and annotation of strain ATCC 49946. The analysis of the sequence and its comparison with sequenced genomes of closely related enterobacteria revealed signs of pathoadaptation to rosaceous hosts.Erwinia amylovora, a plant-associated member of the Enterobacteriaceae, causes fire blight, a devastating disease of rosaceous plants, especially pear and apple (6). The complete genome of Ea273 (ATCC 49946), a virulent strain isolated from an infected apple tree in New York State, was sequenced. Total DNA was extracted and prepared in pMAQ1 shotgun libraries. The complete shotgun sequence was obtained by using dye terminator chemistry in ABI 3730 automated sequencers and contains 88,457 reads (11.12-fold coverage), yielding a theoretical coverage of the genome of 99.99%. The sequence was assembled, finished, and annotated as described previously (1, 5), using Artemis (4) to collate data and facilitate annotation.The genome of E. amylovora consists of a circular chromosome of 3,805,874 bp and two plasmids, AMYP1 (28,243 bp) and AMYP2 (71,487 bp). Coding regions in the chromosome account for 85.1% of the total sequence, with 3,483 identified coding sequences (CDS). Two hundred fifty-four (7%) of the CDSs do not have any matches in current NCBI databases; 114 (3.3%) correspond to conserved hypothetical proteins. Forty-nine CDSs (1.4%) are similar to genes from mobile elements such as integrases, transposases, and bacteriophages, and 110 CDSs (3.2%) were classified as pseudogenes due to interruptions or truncations of the CDSs. The remaining 2,956 annotated CDSs include among other categories genes involved in biosynthesis of the cellular envelope and modifications of surface proteins (299 CDSs [11%]) and genes involved in signal transduction and regulation (228 CDSs [8%]). Seven rRNA operons and 78 tRNA sequences were identified in the chromosome; two new clusters were identified (AMY1550-1575 and AMY2648-2676) that resemble the T3SS-encoding SSR-1 island of Sodalis glossinidius (2), and four clusters that contain genes for biosynthesis of flagella, which based on their location might be regulated independently.The smaller plasmid, AMYP1, had been reported as pEA29 (3); its sequence is nearly identical to the one reported here. The larger plasmid, AMYP2, renamed pEA72 for consistency in nomenclature, contains 87 predicted CDSs, with two predicted mobile-element-related CDSs and one pseudogene. Among the CDSs with annotated functions are a cluster of genes (AMYP2_49 to AMYP2_62) that encode a putative type IV fimbrial system (pil genes).The genome of E. amylovora is only 3.8 Mb long, whereas most free-living enterobacteria, including plant pathogens, have genomes of 4.5 Mb to 5.5 Mb. Comparison of the genome of Ea273 with the sequenced genomes of 15 closely related enterobacteria identified 21 lineage-specific regions, which might be considered genomic islands. E. amylovora has many more predicted pseudogenes, relative to other enterobacteria with similar lifestyles. Given its size and the preponderance of pseudogenes, genome reduction may have occurred via mutational inactivation and subsequent deletion with the following consequences: E. amylovora has fewer genes involved in anaerobic respiration and fermentation than are found in typical related enterobacteria; this likely result in a reduced capacity to live in anaerobic environments.The genome sequence of E. amylovora has revealed clear signs of pathoadaptation to the rosaceous plant environment. For example, T3SS-related proteins are present that are more similar to proteins of other plant pathogens than to proteins of closely related enterobacteria. These include type III effectors, homologous to those of plant-pathogenic pseudomonads, which confer virulence to E. amylovora in plants, and a sorbitol-metabolizing cluster that may confer a competitive advantage for survival in rosaceous plants. The reduced genome size and erosion or loss of genes involved in anaerobic respiration and nitrate assimilation are remarkable, relative to other plant- and animal-pathogenic members of the Enterobacteriaceae.     

Complete Genome Sequence of Klebsiella pneumoniae 1084, a Hypermucoviscosity-Negative K1 Clinical Strain

We report the complete genome sequence of Klebsiella pneumoniae 1084, a hypermucoviscosity-negative K1 clinical strain. Sequencing and annotation revealed a 5,386,705-bp circular chromosome (57.4% G+C content), which contains 4,962 protein-coding genes, 80 tRNA genes, and 25 rRNA genes.     

Complete Genome Sequence of Staphylococcus lugdunensis Strain HKU09-01

Staphylococcus lugdunensis is a member of the coagulase-negative staphylococci and commonly found as part of the human skin flora. It is a significant cause of catheter-related bacteremia and also causes serious infections like native valve endocarditis in previously healthy individuals. We report the complete genome sequence of this medically important bacterium.Staphylococcus lugdunensis is a member of the coagulase-negative staphylococci (CoNS) commonly colonizing the human skin and mucosal membranes. While the genus Staphylococcus contains 48 named species currently, only a few species, notably S. aureus, are coagulase positive. Thus, the phenotypic characteristic is routinely tested in the medical microbiological laboratory for rapid differentiation of the highly pathogenic S. aureus from the other staphylococci. Among the CoNS, only a few species are known to cause human disease, usually in the form of opportunistic infections only (6). However, S. lugdunensis is an important exception (3). Besides causing catheter-related bacteremia similar to other CoNS, it causes a variety of severe nosocomial and community-acquired infections, including native valve endocarditis, a devastating and potentially fatal disease that can affect previously healthy individuals. Another unusual feature are the susceptibilities of S. lugdunensis isolates to multiple antimicrobial agents even when the incidence of multiple-drug-resistant CoNS and S. aureus occurrences are increasing in both hospital and community settings (4, 5).The genome sequence of S. lugdunensis strain HKU09-01 was determined by high-throughput sequencing performed on a GS FLX system (Roche Diagnostics, Basel, Switzerland), with approximately 45-fold coverage of the genome. This clinical strain was previously isolated from the culture of pus from a skin swab. Genome assembly was performed using the Newbler assembler, resulting in 30 large contigs (>500 bp in size). The contigs were then ordered and oriented into one scaffold using OSLay (11). The genome-finishing strategy for S. lugdunensis was similar to that employed for our previously sequenced Laribacter hongkongensis genome (12). Briefly, gap closures were performed by genomic PCR followed by DNA sequencing of amplification products on an ABI 3130xl sequencer (Applied Biosystems, CA). The finished sequence was validated by genome macrorestriction analysis using multiple rare-cutting enzymes and visualization by pulsed-field gel electrophoresis. Protein coding regions were predicted with Glimmer3 (2), and automatic genome annotation was performed on the RAST server (1). Additionally, annotation of tRNA and transfer-messenger RNA (tmRNA) genes was performed using tRNAScan-SE (10) and ARAGORN (9). Identification of rRNA genes was performed using RNAmmer (8).The genome of S. lugdunensis strain HKU09-01 consists of a circular 2,658,366-bp chromosome with G+C content of 33.87%, similar to those of other staphylococci. No plasmids are present in the sequenced strain. The genome contains 61 tRNA genes for all amino acids and 2,489 predicted protein-coding genes. Eight putative genomic islands were identified, and one actually consists of a pair of duplicated 32-kb genomic regions. Similar to Staphylococcus saprophyticus (7), but different from the other staphylococci, the genome contains 6 rRNA operons, one of them having the unusual organization 5S-16S-23S-5S.With the availability of the present genome sequence, S. lugdunensis now joins other staphylococcal species with human pathogenic potential, like S. aureus, S. epidermidis, S. haemolyticus, and S. saprophyticus, to have at least one reference genome available. Further in-depth analysis will be necessary to fully elucidate the genomic differences that may explain the variation in virulence of the staphylococcal species.