Abstract:
:CRISPR-Cas systems are prokaryotic adaptive immune systems that facilitate protection of bacteria and archaea against infection by external mobile genetic elements. The model pathogen Francisella novicida encodes a CRISPR-Cas12a (FnoCas12a) system and a CRISPR-Cas9 (FnoCas9) system, the latter of which has an additional and noncanonical function in bacterial virulence. Here, we investigated and compared the functional roles of the FnoCas12a and FnoCas9 systems in transformation inhibition and bacterial virulence. Unlike FnoCas9, FnoCas12a was not required for F. novicida virulence. However, both systems were highly effective at plasmid restriction and acted independently of each other. We further identified a critical protospacer-adjacent motif (PAM) necessary for transformation inhibition by FnoCas12a, demonstrating a greater flexibility for target identification by FnoCas12a than previously appreciated and a specificity that is distinct from that of FnoCas9. The effectors of the two systems exhibited different patterns of expression at the mRNA level, suggesting that they may confer distinct benefits to the bacterium in diverse environments. These data suggest that due to the differences between the two CRISPR-Cas systems, together they may provide F. novicida with a more comprehensive defense against foreign nucleic acids. Finally, we demonstrated that the FnoCas12a and FnoCas9 machineries could be simultaneously engineered to restrict the same nonnative target, thereby expanding the toolset for prokaryotic genome manipulation.IMPORTANCE CRISPR-Cas9 and CRISPR-Cas12a systems have been widely commandeered for genome engineering. However, they originate in prokaryotes, where they function as adaptive immune systems. The details of this activity and relationship between these systems within native host organisms have been minimally explored. The human pathogen Francisella novicida contains both of these systems, with the Cas9 system also exhibiting a second activity, modulating virulence through transcriptional regulation. We compared and contrasted the ability of these two systems to control virulence and restrict DNA within their native host bacterium, highlighting differences and similarities in these two functions. Collectively, our results indicate that these two distinct and reprogrammable endogenous systems provide F. novicida with a more comprehensive defense against mobile genetic elements.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Ratner HK,Weiss DSdoi
10.1128/JB.00670-19subject
Has Abstractpub_date
2020-05-27 00:00:00issue
12eissn
0021-9193issn
1098-5530pii
JB.00670-19journal_volume
202pub_type
杂志文章abstract::Spontaneous, erythromycin-resistant mutants of Thermus thermophilus IB-21 were isolated and found to carry the mutation A2058G in one of two 23S rRNA operons. The heterozygosity of these mutants indicates that A2058G confers a dominant or codominant phenotype in this organism. This mutation provides a valuable tool fo...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.14.4382-4385.2001
更新日期:2001-07-01 00:00:00
abstract::Pseudomonas sp. strain ACP is capable of growth on 1-aminocyclopropane-1-carboxylate (ACC) as a nitrogen source owing to induction of the enzyme ACC deaminase and the subsequent conversion of ACC to alpha-ketobutyrate and ammonia (M. Honma, Agric. Biol. Chem. 49:567-571, 1985). The complete amino acid sequence of puri...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.173.17.5260-5265.1991
更新日期:1991-09-01 00:00:00
abstract::S1 nuclease mapping and Northern (RNA) hybridization revealed that the rpoDA gene encoding the principal sigma subunit of Pseudomonas aeruginosa PAO1 is transcribed as a monocistronic mRNA of 2 kb and that the transcription from the rpoDA promoter (PC) starts 32 bases upstream from the first nucleotide of the initiati...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.4.1069-1074.1993
更新日期:1993-02-01 00:00:00
abstract::Streptococcus agalactiae cultures possess an aerobic pathway for glucose oxidation that is strongly inhibited by cyanide. The products of glucose oxidation by aerobically grown cells of S. agalactiae 50 are lactic and acetic acids, acetylmethylcarbinol, and carbon dioxide. Glucose degradation products by aerobically g...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.94.1.184-191.1967
更新日期:1967-07-01 00:00:00
abstract::The nucleotide sequence of the Clostridium thermocellum F1 xynC gene, which encodes the xylanase XynC, consists of 1,857 bp and encodes a protein of 619 amino acids with a molecular weight of 69,517. XynC contains a typical N-terminal signal peptide of 32 amino acid residues, followed by a 165-amino-acid sequence whic...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.179.13.4246-4253.1997
更新日期:1997-07-01 00:00:00
abstract::The bacteriocin produced by a strain of Staphylococcus aureus has been isolated and designated staphylococcin (414), and a study was made of its chemical, physical, and biological properties. The staphylococcin is released in appreciable quantities after breakage of the cells and can be purified through differential c...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.104.1.117-125.1970
更新日期:1970-10-01 00:00:00
abstract::Valentine, R. C. (University of Illinois, Urbana), H. Drucker, and R. S. Wolfe. Glyoxylate fermentation by Streptococcus allantoicus. J. Bacteriol. 87:241-246. 1964.-Extracts of Streptococcus allantoicus were found to degrade glyoxylate, yielding tartronic semialdehyde and CO(2). Tartronic semialdehyde was prepared ch...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.87.2.241-246.1964
更新日期:1964-02-01 00:00:00
abstract::The lipopolysaccharide (LPS) from Rhizobium trifolii 0403 was isolated at different stages of growth and was examined for its (i) ability to bind a white clover lectin (trifoliin A), (ii) immunochemical properties, and (iii) composition. There was significantly more binding of trifoliin A to purified LPS and cells in ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.148.2.697-711.1981
更新日期:1981-11-01 00:00:00
abstract::In mycobacterial growth medium 40 to 400 microM citrate was required to solubilize 2 microM 55Fe. This solubilized 55Fe was taken up into both iron-deficient and iron sufficient washed cell suspensions of Mycobacterium smegmatis and Mycobacterium bovis BCG. Although the 55Fe was taken up into the cell, the citrate was...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.149.1.131-135.1982
更新日期:1982-01-01 00:00:00
abstract::The three-component naphthalene dioxygenase (NDO) enzyme system carries out the first step in the aerobic degradation of naphthalene by Pseudomonas sp. strain NCIB 9816-4. The three-dimensional structure of NDO revealed that several of the amino acids at the active site of the oxygenase are hydrophobic, which is consi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.6.1641-1649.2000
更新日期:2000-03-01 00:00:00
abstract::The effect of L-methionine-DL-sulfoximine, an inhibitor of glutamine synthetase, on the formation of nitrate reductase in the wild-type strain of Neurospora in the presence of ammonium ions and of glutamine was studied. Under conditions in which glutamine synthetase was inactivated, it was found that only glutamine co...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.143.1.411-415.1980
更新日期:1980-07-01 00:00:00
abstract::Salmonella typhimurium invasion of nonphagocytic cells requires the expression of a type III secretion system (TTSS) encoded within Salmonella pathogenicity island 1 (SPI1). TTSS gene transcription is activated in response to environmental signals and requires transcriptional regulators encoded within (HilA) and outsi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.181.10.3096-3104.1999
更新日期:1999-05-01 00:00:00
abstract::The thiol-containing tripeptide glutathione is an important cellular constituent of many eukaryotic and prokaryotic cells. In addition to its disulfide reductase activity, glutathione is known to protect cells from many forms of physiological stress. This report represents the first investigation into the role of glut...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01393-12
更新日期:2012-11-01 00:00:00
abstract::The elemental composition of individual cells of rapidly frozen and cryosectioned Escherichia coli B was measured with electron optical microanalytic methods. The Ca content was high (26.2 mmol/kg) in a 10-nm-wide region of the cell envelope. Amounts of cytoplasmic Ca in actively dividing cells were significantly high...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.167.3.935-939.1986
更新日期:1986-09-01 00:00:00
abstract::From the cell envelope preparation of Sphingomonas paucimobilis two membrane fractions with different densities were separated by sucrose density gradient ultracentrifugation. The high-density fraction contained several major proteins, phospholipids, and glycosphingolipids, which are the only glycolipids of this lipop...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.176.2.284-290.1994
更新日期:1994-01-01 00:00:00
abstract::A cosmid vector has been constructed, using a lambda replicon. A library of cosmids from Anabaena variabilis ATCC 29413 based on use of this vector is shown to be highly deficient in sites for the two type II restriction endonucleases found in that organism. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.160.2.781-784.1984
更新日期:1984-11-01 00:00:00
abstract::Previous microarray studies have suggested that an indirect mechanism of Fur regulation may be present in meningococcus at the posttranscriptional level through a small regulatory RNA (sRNA) system analogous to that of Escherichia coli and Pseudomonas aeruginosa. Recently, a Fur-regulated sRNA, NrrF, was identified th...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00849-08
更新日期:2009-02-01 00:00:00
abstract::Pseudomonas putida DOT-T1 was isolated after enrichment on minimal medium with 1% (vol/vol) toluene as the sole C source. The strain was able to grow in the presence of 90% (vol/vol) toluene and was tolerant to organic solvents whose log P(ow) (octanol/water partition coefficient) was higher than 2.3. Solvent toleranc...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.177.14.3911-3916.1995
更新日期:1995-07-01 00:00:00
abstract::The recent discovery that the protein DksA acts as a coregulator of genes controlled by ppGpp led us to investigate the similarities and differences between the relaxed phenotype of a ppGpp-deficient mutant and the phenotype of a strain lacking DksA. We demonstrate that the absence of DksA and ppGpp has similar effect...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00330-07
更新日期:2007-07-01 00:00:00
abstract::Physiological studies of a mutant of Escherichia coli lacking the three lytic transglycosylases Slt70, MltA, and MltB revealed that interference with murein turnover can prevent AmpC beta-lactamase induction. The triple mutant, although growing normally, shows a dramatically reduced rate of murein turnover. Despite th...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.181.23.7192-7198.1999
更新日期:1999-12-01 00:00:00
abstract::We report the draft genome of the strain Lactobacillus gigeriorum CRBIP 24.85(T), isolated from a chicken crop. The total length of the 60 scaffolds is about 1.9 Mb, with a GC content of 38% and 2,062 protein-coding sequences (CDS). ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01427-12
更新日期:2012-11-01 00:00:00
abstract::As with other inducible enzymes, the induced synthesis of l-arabinose isomerase (l-arabinose ketol isomerase, EC 5.3.1.4) in Salmonella typhimurium is subject to catabolite repression. Of the three catabolite repressors tested, glucose produces maximum repression. Analogues of catabolite repressors like 2-deoxy-d-gluc...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.106.1.107-112.1971
更新日期:1971-04-01 00:00:00
abstract::Ubiquitination of intracellular proteins by the yeast RAD6 (UBC2) ubiquitin-conjugating (E2) enzyme is required for cellular processes as diverse as DNA repair, selective proteolysis, and normal growth. For most RAD6-dependent functions, the relevant in vivo targets, as well as the mechanisms and cofactors that govern...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.177.3.580-585.1995
更新日期:1995-02-01 00:00:00
abstract::In Selenomonas ruminantium, a strictly anaerobic and gram-negative bacterium, the degradation of lysine/ornithine decarboxylase (LDC/ODC) by ATP-requiring protease(s) is accelerated by the binding of P22, which is a ribosomal protein of this strain. Amino acid sequence alignment of S. ruminantium P22 with the L10 ribo...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01429-07
更新日期:2008-01-01 00:00:00
abstract::Translational efficiency of an AUG, CUG, GUG, or UUG initiation codon was measured for the naturally leaderless cI mRNA from bacteriophage lambda. In a cI-lacZ translational fusion, only AUG supported a high level of expression; GUG supported a low level of expression, while UUG and CUG expression was barely above bac...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.4.1277-1283.2001
更新日期:2001-02-01 00:00:00
abstract::Metal-dependent superoxide dismutases (SODs) with a specific requirement for a manganese or iron ion for catalytic activity and copper- and zinc-dependent enzymes are essential for detoxification of superoxide anion radicals. Genome sequence analyses predict the existence of a nickel-dependent enzyme (NiSOD) as the un...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.186.22.7821-7825.2004
更新日期:2004-11-01 00:00:00
abstract::The plasmid nature of genes specifying degradation of nicotine and nicotinate in Pseudomas convexa strain 1 (Pc1) is indicated by mitomycin curing and conjugational transfer to other strains. The NIC plasmid appears to be compatible with other metabolic plasmids in Pseudomonas putida. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.135.1.289-290.1978
更新日期:1978-07-01 00:00:00
abstract::A cyclic polyol, 1,5-anhydro-D-glucitol (AG), is widely detected in most organisms, although little is known about its metabolism and physiological roles. The present study demonstrates the synthesis of AG in Escherichia coli C600. The major portion of the synthesized AG was indicated to be derived from glucose retain...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.22.7138-7141.1993
更新日期:1993-11-01 00:00:00
abstract::Overexpression of vsr in Escherichia coli stimulates transition and frameshift mutations. The pattern of mutations suggests that mutagenesis is due to saturation or inactivation of dam-directed mismatch repair. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.14.4294-4296.1996
更新日期:1996-07-01 00:00:00
abstract::Streptococcus faecalis obtains metabolic energy chiefly from the conversion of glucose to lactic acid; the present experiments deal with the mechanism of lactic acid translocation across the cytoplasmic membrane. Efflux of [(14)C]lactate from preloaded cells was accelerated by raising the external pH, and also by the ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.117.3.1141-1148.1974
更新日期:1974-03-01 00:00:00