| pathway of glucose catabolism in caulobacter crescentus. | glucose when present as a sole organic carbon source in a mineral salts medium is dissimilated by caulobacter crescentus atcc 15252 (strain cb-2) by the entner-doudoroff pathway throughout the culture cycle (exponential, transition, and stationary phase). most of the available glucose that is present at the onset of exponential growth is assimilated by the cells during the transition phase or the period associated with stalk cell development. swarmer cell development is minimized during this pha ... | 1976 | 18652 |
| ammonia assimilation and glutamate formation in caulobacter crescentus. | in the dimorphic bacterium caulobacter crescentus, ammonia assimilation occurs only via the combined action of the enzymes glutamine synthetase and glutamate synthase. mutants auxotrophic for glutamate lacked glutamate synthase activity, and the mutations leading to the glutamate auxotrophy appeared to lie at two distinct genetic loci. both glutamate synthase and glutamine synthetase activities were subject to regulation by repression. glutamate synthase activity was highest in cultures grown in ... | 1978 | 22537 |
| purification and characterization of a polyhook protein from caulobacter crescentus. | a polyhook-producing strain of caulobacter crescentus was isolated, and the polyhook protein was purified. the antigenicity and morphology of the polyhook structure are similar to the wild-type hook except that the mutant strain produces a hook structure at least 10-fold the length of wild-type hooks (1.0 versus 0.1 micrometers). the molecular weight of the polyhook protein, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, is 72,000, and the protein has a pi of approxi ... | 1979 | 86537 |
| homology of the gene coding for outer membrane lipoprotein within various gram-negative bacteria. | the mrna for a major outer membrane lipoprotein from escherichia coli was found to hybridize specifically with one of the ecori and one of the hindiii restriction endonuclease-generated fragments of total dna from nine bacteria in the family enterobacteriaceae: e. coli, shigella dysenteriae, salmonella typhimurium, citrobacter freundii, klebsiella aerogenes, enterobacter aerogenes, edwardsiella tarda, serratia marcescens, and erwinia amylovora. however, among the enterobacteriaceae, dna from two ... | 1979 | 104972 |
| [species composition of heterotrophic bacteria in the water of the rybinek reservoir]. | twenty four cultures of heterotrophic bacteria were isolated from the water of the rybinsk reservoir on a medium containing organic matter. bacteria belonging to the families pseudomonadaceae and achromobacteriaceae were most widely distributed; bacteria of the mycobacteriaceae family were encountered less often. predominating species which belonged to the genera pseudomonas, caulobacter, flavobacterium, mycobacterium, and corynebacterium were isolated from the central part of the reservoir. the ... | 1977 | 142898 |
| deoxyribonucleic acid sequence homologies among bacterial insertion sequence elements and genomes of various organisms. | plasmid and phage deoxyribonucleic acid (dna) harboring bacterial insertion sequence (is) elements is1, is2, and is5 were characterized and used as probes to detect homologous sequences in various procaryotic and eucaryotic genomes. the hybridization method used permits the detection of sequences partially homologous to the elements. hybridization of the is-containing probes to each other revealed a region of limited homology between is1 and is2. homologous sequences were then detected by comput ... | 1979 | 159291 |
| regulation of the caulobacter cell cycle. | | 1975 | 164329 |
| a specific cyclic guanosine 3':5'-monophosphate-binding protein in caulobacter crescentus. | a binding protein specific for cyclic guanosine 3':5'-monophosphate (cyclic gmp) has been partially purified from extracts of the eubacterium caulobacter crescentus and resolved from cyclic adenosine 3':5'-monophosphate (cyclic amp)-binding activity. binding of cyclic gmp is not affected by the addition of cyclic amp or 5'-gmp, but is inhibited about 50 percent by a 50-fold molar excess of dibutyryl cyclic gmp or cyclic hypoxanthine 3':5'-monophosphate. the apparent dissociation constant for the ... | 1975 | 168209 |
| effect of 3':5'-cyclic gmp derivatives on the formation of caulobacter surface structures. | exogenous derivatives of 3':5'-cyclic gmp, 8-bromo- and n2,o2'-dibutyryl cyclic gmp, coordinately repress surface structure differentiation in caulobacter crescentus. growth in the presence of cyclic gmp derivatives resulted in the loss of flagella and pili formation and concomitant resistance to both dna phage phicbk and rna phage phicb5 infection without affecting growth rate, stalk formation, and equatorial cell division. the effect of cyclic gmp derivatives was shown to be the repression of ... | 1976 | 184471 |
| differentiation in the caulobacter cell cycle. | | 1976 | 185940 |
| effect of carbon source and the role of cyclic adenosine 3',5'-monophosphate on the caulobacter cell cycle. | the expression of cell cycle events in caulobacter crescentus cb13 has been shown to be associated with regulation of carbohydrate utilization. growth on lactose and galactose depends on induction of specific enzymes. prior growth on glucose results in a delay in enzyme expression and cell cycle arrest at the nonmotile, predivisional stage. dibutyryl cyclic adenosine 3',5'-monophosphate (amp) was shown to stimulate expression of the inducible enzymes and, thus, the initiation of the cell cycle. ... | 1977 | 197060 |
| galactose catabolism in caulobacter crescentus. | caulobacter crescentus wild-type strain cb13 is unable to utilize galactose as the sole carbon source unless derivatives of cyclic amp are present. spontaneous mutants have been isolated which are able to grow on galactose in the absence of exogenous cyclic nucleotides. these mutants and the wild-type strain were used to determine the pathway of galactose catabolism in this organism. it is shown here that c. crescentus catabolizes galactose by the entner-duodoroff pathway. galactose is initially ... | 1978 | 210153 |
| mutational analysis of developmental control in caulobacter crescentus. | the relationship between the cell cycle and control of development has been studied by a genetic analysis of caulobacter crescentus. the behavior of conditional cell division mutants showed that cell cycle events, such as dna replication and cell division, are organized into a dependent pathway(s), i.e., later steps cannot preceed until earlier ones are completed. the ability of these strains to develop normally under nonpermissive conditions suggested that flagellin synthesis and stalk formatio ... | 1977 | 264665 |
| caulobacter crescentus nucleoid: analysis of sedimentation behavior and protein composition during the cell cycle. | the envelope-associated nucleoid (ean) of caulobacter crescentus has been isolated during major developmental stages in the cell cycle. the sedimentation coefficient of the caulobacter ean changes as a function of development and is closely correlated with the periodicity of dna synthesis in this bacterium. the contribution of proteins to the structure of the caulobacter nucleoid has been analyzed by using polyacrylamide gel electrophoresis of proteins labeled both for short intervals and contin ... | 1979 | 284329 |
| cell-cycle-associated rearrangement of inverted repeat dna sequences. | inverted repeat dna sequences of caulobacter crescentus have been isolated, characterized, and cloned in a bacteriophage lambda vector. both whole populations and individual clones of these sequences were hybridized to restriction endonuclease-generated fragments of chromosomal dna isolated from cells that were in different stages of the cell cycle. some inverted repeat dna sequences were observed to hybridize to different regions of the chromosomal dna isolated from the morphologically and bioc ... | 1979 | 293718 |
| caulobacter crescentus rna polymerase. purification and characterization of holoenzyme and core polymerase. | | 1977 | 325002 |
| host factor for coliphage q beta rna replication: presence in procaryotes and association with the 30s ribosomal subunit in escherichia coli. | the host factor required for in vitro coliphage q beta rna replication, a heat-stable rna binding protein present in uninfected escherichia coli, has been detected by both immunological and functional tests in acinetobacter calcoaceticus, klebsiella pneumoniae, pseudomonas aeruginosa and pseudomonas putida. it was not detectable by these criteria in bacillus stearothermophilus, bacillus subtilis, caulobacter crescentus, micrococcus lysodeikticus, rhodopseudomonas capsulata or saccharomyces cerev ... | 1977 | 329101 |
| envelope-associated nucleoid from caulobacter crescentus stalked and swarmer cells. | envelope-associated nucleoids have been isolated from caulobacter crescentus by using a modification of the procedure of t. kornberg et al. (proc. natl. acad. sci. u.s.a. 71:3189-3193, 1974). the development of a ludox density gradient procedure has permitted preparation of large quantities of synchronous cells. the sedimentation coefficients of the envelope-associated nucleoids of stalked and swarmer cells, prepared under conditions of equivalent cell lysis, were 3,000s and greater than 6,000s ... | 1977 | 334726 |
| reconstitution and purification of flagellar filaments from caulobacter crescentus. | filaments from isolated flagella of caulobacter crescentus have been purified by successive dissociation and reconstitution. after the second and third reconstitutions from subunits in 0.8 m sodium citrate, filament preparations contained only two proteins, flagellin a (26,000 daltons) and flagellin b (28,000 daltons). there was some enrichment for flagellin a during reconstitution by this procedure, since isolated flagella contained flagellin a and flagellin b in a ratio of approximately 3.8:1 ... | 1977 | 336599 |
| the absence of translational barrier between caulobacter crescentus and escherichia coli. | | 1978 | 352729 |
| differential transcription of fd rfi dna by caulobacter crescentus and escherichia coli rna polymerases. | | 1979 | 371987 |
| transfer of drug resistance factors to the dimorphic bacterium caulobacter crescentus. | the p-type drug resistance factors rp4, rk2, r702, r68.45, and the n-type drug resistance factor r46 are transferred to caulobacter crescentus at high frequencies. they are stably maintained and their antibiotic resistances are expressed. experiments with rp4 have shown that intergeneric transfer of rp4 occur at a frequency of 10(-1). c. crescentus strains maintain rp4 as a plasmid, are sensitive to rp4-specific phage, and segregate phage-resistant cells at a frequency of 10(-4) to 10(-5). the r ... | 1979 | 378764 |
| effect of macromolecular synthesis on the coordinate morphogenesis of polar surface structures in caulobacter crescentus. | the caulobacter polar surface structures (flagella, pili, and the deoxyribonucleic acid phage phicbk receptors), which are expressed at proximal sites of swarmer cells in a coordinate manner (shapiro, annu. rev. microbiol., 30:377-407, 1976) could be blocked by a single mutation. the mutant c. crescentus cb13 ple-801 did not form these surface structures when grown at 35 degrees c. upon shift down to 25 degrees c, the mutant cells initiated the formation of the surface structures. when mitomycin ... | 1977 | 405372 |
| transfer and expression of pseudomonas plasmid rp1 in caulobacter. | this study demonstrates that the host range of pseudomonas plasmid rp1 includes the genus caulobacter. caulobacter was shown to acquire three antibiotic resistance markers located in rp1. a fourth plasmid marker, susceptibility to an rna bacteriophage, was not expressed, but could be transferred from caulobacter to escherichia coli. the lack of phenotypic expression of the phage marker was manifested by the inability of the phage to adsorb or to produce plaques on caulobacter transcipients. mati ... | 1977 | 406354 |
| isolation of spontaneously derived mutants of caulobacter crescentus. | caulobacter crescentus has a penicillinase which precludes the use of penicillin for mutant enrichment. however, two other antibiotics, fosfomycin and d-cycloserine, can be enrich for c. crescentus mutants. in enrichment procedures for c. crescentus auxotrophs, spontaneously derived mutants occur at a frequency of 5-10% among the survivors of an enrichment procedure. consequently, large numbers of mutants are readily obtained without any need for mutagenesis. these mutants are heterogeneous both ... | 1977 | 407126 |
| properties of unprimed poly(a)-poly(u) synthesis by caulobacter crescentus rna polymerase. | some properties of unprimed poly(a)-poly(u) synthesis by dna-dependent rna polymerase from caulobacter crescentus were examined. the reaction required atp and utp as substrates and manganese as a divalent cation. rifampicin completely inhibited the reaction at a concentration of 1 micron/ml, and the enzyme catalyzed the polymer synthesis well regardless of the presence of gtp, ctp or both. the chain length of the poly(a)-poly(u) synthesized was about one hundred base pairs, as estimated from a s ... | 1979 | 429257 |
| comparative study of the aerobic, heterotrophic bacterial flora of chesapeake bay and tokyo bay. | a comparative study of the bacterial flora of the water of chesapeake bay and tokyo bay was undertaken to assess similarities and differences between the autochthonous flora of the two geographical sites and to test the hypothesis that, given similarities in environmental parameters, similar bacterial populations will be found, despite extreme geographic distance between locations. a total of 195 aerobic, heterotrophic bacterial strains isolated from chesapeake bay and tokyo bay water were exami ... | 1979 | 453838 |
| phospholipids of the differentiating bacterium caulobacter crescentus. | the phospholipid composition of the stalked and swarmer cell types of the differentiating, gram-negative bacterium caulobacter crescentus was determined. the phospholipid composition of the stalked cell type was 86.5% phosphatidylglycerol, 10.4% lysylphosphatidylglycerol, and 3.0% cardiolipin; that of the swarmer cell type was 84.1, 11.4, and 4.4% respectively. phosphatidylethanolamine, which is a major phospholipid component of most gram-negative bacteria, was totally absent. | 1979 | 455120 |
| flagellar hook and basal complex of caulobacter crescentus. | intact bacterial flagella possessing a membrane-free hook and basal complex were purified from caulobacter crescentus cb15, as well as from mutants which synthesize incomplete flagella. the basal body consisted of five rings mounted on a rod. two rings were in the hook-proximal upper set, and three rings (two narrow and one wide) were in the lower set. the diameters of the two upper rings differed, being 32 and 21 nm, respectively. the lower rings were all approximately 21 nm in diameter, althou ... | 1979 | 457596 |
| generation of asymmetry during development. segregation of type-specific proteins in caulobacter. | an essential event in developmental processes is the introduction of asymmetry into an otherwise undifferentiated cell population. cell division in caulobacter is asymmetric; the progeny cells are structurally different and follow different sequences of development, thus providing a useful model system for the study of differentiation. because the progeny cells are different from one another, there must be a segregation of morphogenetic and informational components at some time in the cell cycle ... | 1979 | 479286 |
| caulobacter cresentus mutant defective in membrane phospholipid synthesis. | to study the relationship between phospholipid synthesis and organelle biogenesis in the dimorphic bacterium caulobacter crescentus, auxotrophs have been isolated which require exogenous glycerol or glycerol 3-phosphate for growth when glucose is used as the carbon source. upon glycerol deprivation, net phospholipid synthesis ceased immediately in a glycerol 3-phosphate auxotroph which was shown to have levels of biosynthetic sn-glycerol 3-phosphate dehydrogenase (e.c. 1.1.1.8) activity 10 times ... | 1979 | 500564 |
| transcription in vitro on isolated caulobacter nucleoids [proceedings]. | | 1979 | 535652 |
| characterization of unstable poly (a)-rna in caulobacter crescentus. | a significant amount of poly(a)-rna in caulobacter crescentus is located on polysomes and the size distribution of this polysomal poly(a)-rna is small compared to the total pulse-labeled rna in these cells. these observations suggest that the poly (a)-rna represents a subset of small messenger rna molecules. poly (a)-rna, and presumably the poly (a) portion of these molecules is extremely unstable: as assayed by binding to oligo (dt)-cellulose the poly (a)-rna turns over with a chemical half-lif ... | 1978 | 623764 |
| caulobacter crescentus cell envelope: effect of growth conditions on murein and outer membrane protein composition. | the murein and membrane protein compositions of caulobacter crescentus strains cb13b1a and cb15 have been characterized, and the influence on cell envelope constituents of culture conditions which affect morphogenesis have been studied. amino acid and sugar analysis of murein sacculi revealed a simple a1gamma murein configuration typical of gram-negative bacteria. the membranes of c. crescentus had low levels of 2-keto-3-deoxyoctonate relative to enteric bacteria, in addition to the absence of l ... | 1978 | 627539 |
| polyadenylic acid synthesis activity of purified dna-dependent rna polymerase from caulobacter. | characterization of purified dna-dependent rna polymerase (ec 2.7.7.6) of caulobacter crescentus, strain cb15 has led to the conclusion that this enzyme catalyzes poly(a) synthesis in the absence of template. poly(a) synthetase activity co-purifies with both holoenzyme and core polymerase on dna-cellulose columns, and core polymerase purified to 98% homogeneity by glycerol gradient centrifugation is still capable of catalyzing poly(a) polymerization. both rna synthesis and poly(a) polymerization ... | 1978 | 632267 |
| regulation of cell cycle events in asymmetrically dividing cells: functions required for dna initiation and chain elongation in caulobacter crescentus. | to study the regulation of cell cycle events after asymmetric cell division in caulobacter crescentus, we have identified functions that are required for dna synthesis in the stalked cell produced at division and in the new stalked cell that develops from the swarmer cell 60 min after division. the initiation of dna synthesis in the two progeny cells is dependent upon at least two common functions. one of these is a requirement for protein synthesis and the other is a gene product identified in ... | 1978 | 670147 |
| rate of major protein synthesis during the cell cycle of caulobacter crescentus. | the rate of major protein synthesis was examined during the synchronous differentiation of caulobacter crescentus. total cell proteins were pulse-labeled with [35s]methionine at different times in the swarmer cell cycle and analyzed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis. the rates of synthesis of total cell proteins and of about one-half of the individual major proteins examined increased through g1 and s periods but remained nearly constant during g2 period. the rates of ... | 1978 | 681285 |
| caulobacter flagellar organelle: synthesis, compartmentation, and assembly. | in caulobacter crescentus biogenesis of the flagellar organelle occurs during one stage of its complex life cycle. thus in synchronous cultures it is possible to assay the sequential synthesis and assembly of the flagellum and hook in vivo with a combination of biochemical and radioimmunological techniques. the periodicity of synthesis and the subcellular compartmentation of the basal hook and filament subunits were determined by radioimmune assay procedures. unassembled 27,000-dalton (27k) flag ... | 1978 | 690070 |
| membrane phospholipid composition of caulobacter crescentus. | the phospholipid composition of caulobacter crescentus cb13 and cb15 was determined. the acidic phospholipids, phosphatidylglycerol and cardiolipin, comprise approximately 87% of the total phospholipids. neither phosphatidylethanolamine nor its precursor phosphatidylserine was detected. the outer and inner membranes of c. crescentus cb13 were separated, and phospholipid analysis revealed heterogeneity with respect to the relative amounts of phosphatidylglycerol and cardiolipin in the two membran ... | 1978 | 690071 |
| selection for nonbuoyant morphological mutants of caulobacter crescentus. | morphological mutants of caulobacter crescentus were isolated by selecting for cells that did not possess normal, buoyancy-conferring stalks. the most prevalent phenotype enriched by the selection was structurally deficient stalks (designated "cds"), observable as crumpled or flattened stalks. the second phenotype ("abs") was observed as spontaneous shedding of normal-appearing stalks. third, one mutant ("ecs") was isolated that sheds not only stalks, but also miniature stalked and nonstalked ce ... | 1978 | 690072 |
| the terminal bases of ribonucleic acid from caulobacter rna phage phicp2. | the terminal bases of the viral ribonucleic acid from the caulobacter ribonucleic acid phage phicp2 were examined. the viral ribonucleic acid contained guanosine triphosphate (pppg) at the 5'-terminus and adenosine (aoh) at the 3'-terminus. | 1978 | 690100 |
| isolation and characterization of caulobacter crescentus flagellar hooks. | the basal hook structure of the flagellar organelle caulobacter crescentus was isolated from release flagella. hook preparations contained a single major proteins species of 73,000 molecular weight and proteins in smaller amounts that may be minor hook components. hooks isolated from c. crescents cb13b1a and cb15 were immunologically cross-reactive. | 1978 | 711679 |
| characterization of two flagella-related proteins from caulobacter crescentus. | | 1978 | 720608 |
| analysis of nonmotile mutants of the dimorphic bacterium caulobacter crescentus. | a total of 69 spontaneous nonmotile mutants were isolated from the dimorphic bacterium caulobacter crescentus. the majority of the mutants were unable to assemble a flagellar filament (fla-), although eight were able to synthesize a short stub of a flagellum. a third mutant class assembled flagella of normal morphology but were nonmotile (mot-). genetic analysis by phicr30-mediated transduction revealed 27 linkage groups for the fla and stub-forming mutations, and three linkage groups for the mo ... | 1979 | 762024 |
| pattern of unequal cell division and development in caulobacter crescentus. | | 1975 | 805732 |
| terminal-sequence analysis of bacterial ribosomal rna. correlation between the 3'-terminal-polypyrimidine sequence of 16-s rna and translational specificity of the ribosome. | the 3'-terminal sequences of 16-s ribosomal rna from a number of bacteria have been determined by a stepwise degradation and 3'-terminal labelling procedure. the sequences obtained were: bacillus stearothermophilus, -g(z)approximately 5 y-u-c-c-u-u-u-c-u (a); b. subtilis, -g(z)approximately 7 y-c-u-u-u-c-u; caulobacter crescentus, -g(z)3 y-u-c-c-u-u-u-c-u; pseudomonas aerugionosa, -g-z-z-y-c-u-c-u-c-c-u-u(a), where z is any nucleotide other than g. thus, as previously found in escherichia coli, ... | 1975 | 809282 |
| physical characterization of caulobacter crescentus flagella. | preparations of intact flagella isolated from caulobacter crescentus cb13b1a were found to contain two protein species of apparent molecular weights 28,000 and 25,000. both proteins cross-reacted completely with each other and with purified flagella in ouchterlony double-immunodiffusion assays. the amino acid compositions of the isolated proteins were similar to one another but precluded any precursor-product relationship. absence of both the 25,000- and 28,000-molecular-weight proteins from a n ... | 1976 | 824276 |
| adsorption properties of stage-specific caulobacter phage phicbk. | | 1977 | 841867 |
| chromosome replication in caulobacter crescentus growing in a nutrient broth. | the pattern of chromosome replication in the caulobacter crescentus cell cycle was studied by examining the rate of deoxyribonucleic acid (dna) synthesis during synchronous growth in a fast-growth nutrient broth. as reported previously for the cell cycle in a slow-growth minimal medium (degnen and newton, 1972), the caulobacter cell cycle (at the fastest available growth rate) in nutrient broth consisted of three distinct periods in terms of dna synthetic activity. the swarmer-cell cycle consist ... | 1977 | 845114 |
| patterns of protein synthesis during development in caulobacter crescentus. | | 1977 | 849807 |
| ribosomal ribonucleic acid cistron homologies among hyphomicrobium and various other bacteria. | the extent of hybrid formation between the ribosomal ribonucleic acid (r-rna) of hyphomicrobium strain b-522 and deoxyribonucleic acid (dna) from bacteria of 21 different genera was examined. three generalized groupings were formed. group i (72-100%) consisted entirely of other strains of hyphomicrobium. representatives of the genera rhodopseudomonas, chromatium, caulobacter, prosthecomicrobium, rhodomicrobium, hyphomonas, and hyphomicrobium made up group ii (49-69%). the remaining gram-negative ... | 1977 | 861853 |
| stalkless mutants of caulobacter crescentus. | a stalk, a single falgellum, several pili, and deoxyribonucleic acid (dna) phage receptors are polar surface structures expressed at a defined time in the caulobacter crescentus cell cycle. when mutants were isolated as dna phage phicbk-resistant or ribonucleic acid (rna) phage phicp2-resistant, as well as nonmotile, strains, 5 out of 30 such mutant isolates were found not to possess stalks, but did possess inactive flagella. these stalkless mutants were resistant simultaneously to both dna and ... | 1977 | 873885 |
| caulobacter crescentus pili: structure and stage-specific expression. | pili are functionally expressed during the predivisional and swarmer stages of the caulobacter crescentus differentiation cycle. they appear on the developing swarmer pole and at the same cellular location as flagella and the phicbk receptor sites. pili disappear when the swarmer cell differentiates into a stalked cell; this occurs with the loss of flagella and the disappearance of phage receptor sites. c. crescentus cb13b1a pili have been purified and characterized. monomeric pilin is a protein ... | 1977 | 873890 |
| gamma-ray sensitivity during synchronous cell differentiation in caulobacter crescentus. | gamma-ray sensitivity of caulobacter crescentus during its cell cycle was examined. survival curves of the swarmer and stalked cells were similar and exponential in shape, whereas that of the predivisional cell was sigmoidal, with an extrapolation number of 1.8. | 1977 | 873892 |
| regulation of flagellin synthesis in the cell cycle of caulobacter: dependence on dna replication. | synthesis of the two filament proteins (flagellin a and flagellin b) of the caulobacter creascentus flagellum was measured during the cell cycle. synchronous cells were pulse-labeled with 36s-methionine, and flagellin proteins were isolated from crude extracts by radioimmune precipitation. the results showed that both proteins are maximally induced during the g2 period and that their induction requires de novo transcription. flagellin a, however, continues to be made in the progeny swarmer cells ... | 1977 | 912749 |
| caulobacter flagellins. | flagellins from 17 caulobacter strains were partially purified. their molecular weights and immunological properties indicated that a two-component flagellin system is common among caulobacters. | 1977 | 914783 |
| a flagellotropic bacteriophage and flagella formation in caulobacter. | | 1976 | 936475 |
| structure of caulobacter deoxyribonucleic acid. | the deoxyribonucleic acid of the dimorphic bacterium caulobacter crescentus contains a component that renatures with rapid, unimolecular kinetics. this component was present in both swarmer and stalked cells and exhibited the sensitivity to endonuclease s1 expected for hairpin loops. double-stranded side branches between 100 and 600 nucleotide pairs in length were visible in electron micrographs of rapidly reassociating deoxyribonucleic acid isolated by hydroxyapatite chromatography. no extrachr ... | 1976 | 947891 |
| isolation and characterization of rna phages for caulobacter crescentus. | | 1976 | 960574 |
| requirement for cellular associations in the development of caulobacter crescentus. | | 1976 | 962922 |
| requirement of a cell division step for stalk formation in caulobacter crescentus. | penicillin g at low concentrations blocked cell division in caulobacter crescentus without inhibiting cell growth. the long filamentous cells formed after two to three generations under these conditions had a stalk at one pole and usually one or more flagella at the opposite pole. the failure of the filaments to form a second stalk at the flagellated pole indicates that stalk formation was dependent upon completion of a step that was also required for cell division. two observations support this ... | 1976 | 977541 |
| conditional surface structure mutants of caulobacter crescentus temperature-sensitive flagella formation due to an altered flagellin monomer. | | 1976 | 1003462 |
| regulation of polar surface structures in caulobacter crescentus: pleiotropic mutations affect the coordinate morphogenesis of flagella, pili and phage receptors. | a large number of caulobacter mutants resistant to dna or rna phages were isolated. these phage-resistant mutants exhibited phenotypic variations with respect to cell motility and sensitivity to other phages. the majority of the mutants was resistant to both dna and rna phages tested. in addition, these mutants were either motile or non-motile. the analysis of spontaneous revertants from these mutants indicated that a single mutation is involved in these phenotypic variations. other mutants were ... | 1976 | 1012268 |
| fatty acid composition of selected prosthecate bacteria. | the cellular fatty acid composition of 14 strains of caulobacter speices and types, two species of prosthecomicrobium, and two species of asticcacaulis was determined by gas-liquid chromatography. in most of these bacteria, the major fatty acids were octadecenoic acid (c18:1), hexadecenoic acid (c16:1) and hexadecanoic acid (c16:0). some cyclopropane and branched chain fatty acids were detected in addition to the straight chained acids. hydroxytetradecanoic acid was an important component of p.e ... | 1976 | 1015941 |
| amino acid composition of peptidoglycan in caulobacter crescentus. | peptidoglycan of a gram-negative stalked bacterium, caulobacter crescentus cb13, contained alanine, diaminopimelic acid, and glutamic acid, in molar ratios of 2 : 1 : 1. the amino acid compositions of peptidoglycans isolated from cultures enriched in swarmer and stalked cells, and from a stalk-less mutant were similar. this finding conflicts with a previous observation that swarmer peptidoglycan does not contain diaminopimelic acid (goodwin and shedlarski (1975) arch. biochem. biophys. 170, 23-3 ... | 1976 | 1018023 |
| prosthecobacter fusiformis nov. gen. et sp., the fusiform caulobacter. | four strains of heterotrophic, fusiform caulobacters have been isolated from freshwater sources. a single prostheca extends from one pole of mature cells, and cells attach to various substrata by means of a holdfast located at the distal tip of the appendage. thus, superficially these bacteria bear a strong resemblance to bacteria in the genus caulobacter. however, unlike caulobacter these bacteria do not exhibit a dimorphic life cycle of motile, non-stalked daughter cells and immotile, stalked ... | 1976 | 1086646 |
| ribosomal protein s1 and polypeptide chain initiation in bacteria. | among several subspecies of 30s subunits of escherichia coli observed by polyacrylamide-agarose gel electrophoresis, only the slow-moving, protein s1-containing subspecies participates in the formation of the 30s initiation complex with coliphage ms2 rna as mrna; the other subspecies retain activity with aug as mrna; they are also active in the poly(u)-directed binding of phe-trna. protein s1 from caulobacter crescentus substitutes for e. coli s1 despite the fact that c. crescentus ribosomes do ... | 1975 | 1094462 |
| poly(adenylic acid) sequences in the rna of caulobacter crescenus. | poly(adenylic acid) sequences have been isolated from the gram-negative bacterium caulobacter crescentus. most of these a-rich tracts are associated with large rna molecules that constitute an important fraction of the unstable rna in these bacteria, and, as estimated by poly(u) filter binding, they are not present in the 16s or 23s ribosomal rna. preliminary estimates of size from polyacrylamide gel electrophoresis suggest that the majority of the a-rich tracts ranges from 15 to approximately 5 ... | 1975 | 1094464 |
| gene transfer in caulobacter crescentus: polarized inheritance of genetic markers. | recombination frequencies were determined for 15 independently isolated auxotrophs of c. crescentus crossed pairwise in all possible combinations. the results indicate that the mutants may be grouped into at least two types: "fertile" strains, which recombine with all other mutants at frequencies ranging from less than 10-6 to 3 times 10-2, and "nonfertile" strains which recombine with fertile strains at high frequencies and with other nonfertile strains at low or negligible frequencies. several ... | 1975 | 1137965 |
| purification of cell wall peptidoglycan of the dimorphic bacterium caulobacter crescentus. | | 1975 | 1164030 |
| polarity of gene transfer in caulobacter. | | 1975 | 1202158 |
| synchronous cell differentiation in caulobacter crescentus. | the growth of a stalked bacterium, caulobacter crescentus, has been synchronized easily and reproducibly by a new method. when this bacterium is grown to a late log phase in nutrient broth at 30 c with aeration, swarmer cells are accumulated in the culture to 80% of the whole cell population. when this culture is inoculated into fresh pre-warmed broth at twentyfold dilution, it immediately initiates synchronous cell growth. simultaneously, synchronous cell differentiation is monitored by the sus ... | 1975 | 1230510 |
| effect of cis-platinum(ii)diamminodichloride on cell division of hyphomicrobium and caulobacter. | low concentrations of the radiomimetic agent cis-platinum(ii)diamminodichloride (pdd) inhibited cell division in caulobacter crescentus (0.1 mug/ml) and hyphomicrobium sp. strain b-522 (1.0 mug/ml) without altering the length of prosthecae. after exposure, cells of c. crescentus appeared as long filaments, whereas only the bud portion of hyphomicrobium underwent elongation. pdd-treated cells of both species were multinucleated. after the removal of pdd by washing, filaments of c. crescentus frag ... | 1976 | 1245459 |
| isolation and characterization of caulobacter crecentus bacteriophage phi cd1. | a dna-containing bacteriophage, phicd1, was isolated from sewage and shown to infect both stalked and swarmer cells of caulobacter crescentus strain cb13b1a. phicd1 is a small, icosohedral bacteriophage, 60 nm in diameter, which possesses a short, noncontractile tail, 10 to 12 nm in length. the bacteriophage particle is composed of at least eight structural proteins. phicd1 nucleic acid exists as a linear duplex of dna as judged by: (i) thermal denaturation (tm), (ii) cscl density gradient centr ... | 1976 | 1255848 |
| early caulobacter crescentus genes flil and flim are required for flagellar gene expression and normal cell division. | the biogenesis of the caulobacter crescentus polar flagellum requires the expression of more than 48 genes, which are organized in a regulatory hierarchy. the flbo locus is near the top of the hierarchy, and consequently strains with mutations in this locus are nonmotile and lack the flagellar basal body complex. in addition to the motility phenotype, mutations in this locus also cause abnormal cell division. complementing clones restore both motility and normal cell division. sequence analysis ... | 1992 | 1315735 |
| the control of timing and spatial organization during caulobacter cell differentiation. | | 1992 | 1365874 |
| expression of an early gene in the flagellar regulatory hierarchy is sensitive to an interruption in dna replication. | genes involved in the biogenesis of the flagellum in caulobacter crescentus are expressed in a temporal order and are controlled by a trans-acting regulatory hierarchy. strains with mutations in one of these genes, flas, cannot transcribe flagellar structural genes and divide abnormally. this gene was cloned, and it was found that its transcription is initiated early in the cell cycle. subclones that restored motility to flas mutants also restored normal cell division. although transcription of ... | 1992 | 1372311 |
| biochemical and antigenic properties of the campylobacter flagellar hook protein. | the flagellar filament-hook complex was removed from campylobacter cells by shearing and was purified by differential solubilization and ultracentrifugation at ph 11 followed by cesium chloride buoyant density ultracentrifugation. flagellar filaments were then dissociated in 0.2 m glycine-hcl (ph 2.2), and purified hooks were collected by ultracentrifugation. the hooks (105 by 24 nm) each displayed a conical protrusion at the proximal end, a concave cavity at the distal end, and helically arrang ... | 1992 | 1375929 |
| a developmentally regulated caulobacter flagellar promoter is activated by 3' enhancer and ihf binding elements. | the transcription of a group of flagellar genes is temporally and spatially regulated during the caulobacter crescentus cell cycle. these genes all share the same 5' cis-regulatory elements: a sigma 54 promoter, a binding site for integration host factor (ihf), and an enhancer sequence, known as the ftr element. we have partially purified the ftr-binding proteins, and we show that they require the same enhancer sequences for binding as are required for transcriptional activation. we have also pa ... | 1992 | 1392079 |
| nucleotide sequence analysis of the gene encoding the caulobacter crescentus paracrystalline surface layer protein. | the entire nucleotide sequence of the rsaa gene, encoding the paracrystalline surface (s) layer protein (rsaa) of caulobacter crescentus cb15a, was determined. the rsaa gene encoded a protein of 1026 amino acids, with a predicted molecular weight of 98,132. protease cleavage of mature rsaa protein and amino acid sequencing of retrievable peptides yielded two peptides: one aligned with a region approximately two-thirds the way into the predicted amino acid sequence and the second peptide correspo ... | 1992 | 1393820 |
| the caulobacter crescentus flafg region regulates synthesis and assembly of flagellin proteins encoded by two genetically unlinked gene clusters. | at a specific time in the caulobacter crescentus cell cycle, a single flagellar filament and multiple receptor sites for the swarmer-specific phage phi cbk are assembled at one pole of the predivisional cell. one cluster of genes required for this morphogenesis, the flayg region, includes the flgjkl genes, which encode structural proteins of the flagellar filament. these flagellin genes are flanked by genes required for filament assembly, the flaye genes at one end and the flaf-flbt-flba-flag ge ... | 1992 | 1400155 |
| a three-start helical sheath on the flagellar filament of caulobacter crescentus. | an unusual feature in preparations of the caulobacter crescentus flagellar filaments is that some filaments are surrounded by a set of three windings that form a sheath. we provide evidence that the sheath is composed of subunits having a molecular mass of 24,000 da. we suggest that the sheath could be composed of protofilaments of flagellin wound around the filament. | 1992 | 1400169 |
| the s-layer of caulobacter crescentus: three-dimensional image reconstruction and structure analysis by electron microscopy. | the regular surface protein structure (s-layer) of caulobacter crescentus was analyzed by electron microscopy and three-dimensional image reconstruction to a resolution of 2 nm. projections showed that the s-layer is an array of ring structures, each composed of six subunits that are arranged on a lattice with p6 symmetry. three-dimensional reconstructions showed that the ring subunits were approximately rod-shaped structures and were perpendicular to the plane of the array, with a linker arm em ... | 1992 | 1400205 |
| a histidine protein kinase homologue required for regulation of bacterial cell division and differentiation. | differentiation in the dimorphic bacterium caulobacter crescentus results from a sequence of discontinuous, stage-specific events that leads to the production of a stalked cell and a new motile swarmer cell after each asymmetric cell division. as reported previously, pseudoreversion analysis of mutations in the pleiotropic developmental gene plec identified three cell division genes: divj, divk, and divl. we show here that one of these genes, divj, encodes a predicted protein of 596 residues wit ... | 1992 | 1438215 |
| regulation of cell surface polarity from bacteria to mammals. | the generation of unique domains on the cell, cell surface polarity, is critical for differentiation into the diversity of cell structures and functions found in a wide variety of organisms and cells, including the bacterium caulobacter crescentus, the budding yeast saccharomyces cerevisiae, and mammalian polarized epithelial cells. comparison of the mechanisms for establishing polarity in these cells indicates that restricted membrane protein distributions are generated by selective protein tar ... | 1992 | 1439806 |
| genetics of campylobacter and helicobacter. | this article reviews the current state of genetic analysis of campylobacter and helicobacter. chromosomal genes cloned from campylobacter and helicobacter species are listed along with the method used to identify the cloned gene. campylobacter plasmid genes that have been cloned and expressed in escherichia coli and that specify resistance to tetracycline, kanamycin, or chloramphenicol are presented. this review also examines our current knowledge of genetic exchange in campylobacter, including ... | 1992 | 1444260 |
| identification, isolation, and structural studies of the outer membrane lipopolysaccharide of caulobacter crescentus. | the lipopolysaccharide (lps) of the outer membrane of caulobacter crescentus was purified and analyzed. two distinct strains of the species, na 1000 and cb2a, were examined; despite differences in other membrane-related polysaccharides, the two gave similar lps composition profiles. the lps was the equivalent of the rough lps described for other bacteria in that it lacked the ladder of polysaccharide-containing species that results from addition of variable amounts of a repeated sequence of suga ... | 1992 | 1447131 |
| a temporally controlled sigma-factor is required for polar morphogenesis and normal cell division in caulobacter. | the transcription of many spatially and temporally controlled flagellar structural genes in caulobacter requires the rna polymerase sigma 54 subunit. like flagellar biogenesis, stalk formation is an asymmetric polar morphogenesis that occurs once each cell cycle in response to internal cell cycle signals. we have isolated the sigma 54 gene (rpon) and describe here a novel role for this alternative sigma-factor in cell differentiation: it is required for the biogenesis of both polar structures, a ... | 1992 | 1459461 |
| organization and ordered expression of caulobacter genes encoding flagellar basal body rod and ring proteins. | the biogenesis of the polar flagellum in caulobacter crescentus is limited to a specific time in the cell cycle and to a specific site on the cell. the basal body is the first part of the flagellum to be assembled. in this report we identify a cluster of genes encoding basal body components and describe their transcriptional regulation. the genes in this cluster form an operon whose expression is controlled temporally. the first two genes encode homologs of flgf and flgg, which are the proximal ... | 1992 | 1474584 |
| production of a monoclonal antibody that recognizes the lipopolysaccharide of a campylobacter-like organism. | a monoclonal antibody was produced to a campylobacter-like organism (rmit 32a) which was isolated from the terminal ileum of a pig with proliferative enteritis. isotyping of the antibody revealed that it was an igg2a with kappa light chains. immunoblots using the antibody against proteinase-k-treated whole cell lysates of rmit 32a, a selection of campylobacter species and other enteric bacteria showed that the antibody was specific for rmit 32a and was directed against the lipopolysaccharide. th ... | 1992 | 1474931 |
| cell-cycle control of a cloned chromosomal origin of replication from caulobacter crescentus. | caulobacter crescentus cell division is asymmetric and yields distinct swarmer cell and stalked cell progeny. only the stalked cell initiates chromosomal replication, and the swarmer cell must differentiate into a stalked cell before chromosomal dna replication can occur. in an effort to understand this developmental control of replication, we employed pulsed-field gel electrophoresis to localize and to isolate the chromosomal origin of replication. the c. crescentus homologues of several escher ... | 1992 | 1518064 |
| isolation and comparison of the paracrystalline surface layer proteins of freshwater caulobacters. | several methods for isolation of the paracrystalline surface (s) layer protein (rsaa) of caulobacter crescentus cb15a were evaluated. treatment of cells with hepes (n-2-hydroxyethylpiperazine-n'-2-ethanesulfonic acid) buffer at ph 2 was the most effective means of selectively removing rsaa from cells, and after neutralization, the protein was capable of reassembling into a paracrystalline structure. ethylene glycol-bis(beta-aminoethyl ether)-n,n,n',n'-tetraacetic acid treatment could also be use ... | 1992 | 1548228 |
| the phylogeny of marine and freshwater caulobacters reflects their habitat. | caulobacter is a distinctive genus of prosthecate bacteria. because caulobacters adhere to surfaces and are found in diverse locales, their role in oligotrophic environments and bacterial biofilm communities is of interest. the phylogenetic relationships of a group of marine and freshwater caulobacters were examined in part to address whether the taxonomic grouping of these bacteria (based primarily on morphological characters) was consistent with 16s rrna sequence divergence. the caulobacters e ... | 1992 | 1551840 |
| dna sequence of the 3' end of the caulobacter crescentus 16s rrna gene. | | 1992 | 1561102 |
| expression of the mosquitocidal toxins of bacillus sphaericus and bacillus thuringiensis subsp. israelensis by recombinant caulobacter crescentus, a vehicle for biological control of aquatic insect larvae. | in the quest for effective control of mosquitoes, attention has turned increasingly to strains of the bacteria bacillus sphaericus and bacillus thuringiensis subsp. israelensis, which produce potent toxins with specific mosquitocidal activities. however, sedimentation of the bacterial spores limits the duration of effective control after field application of these bacilli. we describe here the cloning of genes encoding the 51.4- and 41.9-kda toxins from b. sphaericus 2297, the 100-kda toxin from ... | 1992 | 1575492 |
| polar localization of a bacterial chemoreceptor. | the bacterial chemotaxis signal transducer mcp is an integral membrane receptor protein. the chemoreceptor is localized at the flagellum-bearing pole of caulobacter crescentus swarmer cells. amino-terminal sequences of the mcp target the protein to the membrane while the carboxy-terminal portion of the protein is responsible for polar localization. the c. crescentus and escherichia coli mcps have highly conserved carboxy-terminal domains, and when an e. coli mcp is expressed in c. crescentus, it ... | 1992 | 1577276 |
| molecular genetics of the flgi region and its role in flagellum biosynthesis in caulobacter crescentus. | the differentiating bacterium caulobacter crescentus has been studied extensively to understand how a relatively simple life form can govern the timing of expression of genes needed for the production of stage-specific structures. in this study, a clone containing the 5.3-kb flap region was shown to contain the flgi, chel, and flby genes arranged in an operon with transcription proceeding from flgi to flby. the predicted flgi polypeptide shows remarkable identity (44%) to the flagellar basal bod ... | 1992 | 1597425 |
| cell cycle regulation in bacteria. | significant progress has been made in the study of ftsz expression and the topology of ftsz protein localization in escherichia coli cells. exciting results on the identification of new genes required for chromosome resolution and partitioning after the completion of dna synthesis have also been reported. a recent area of study is asymmetric cell division and its role in differentiation in bacillus subtilis and caulobacter crescentus. biochemical activities of bacterial cell division gene produc ... | 1992 | 1599688 |
| molecular and functional characterization of the salmonella invasion gene inva: homology of inva to members of a new protein family. | one of the earliest steps in the pathogenic cycle of the facultative intracellular pathogen salmonella spp. is the invasion of the cells of the intestinal epithelium. we have previously identified a genetic locus, inv, that allows salmonella spp. to enter cultured epithelial cells. inva is a member of this locus, and it is the first gene of an operon consisting of at least two additional invasion genes. we have constructed strains carrying nonpolar mutations in inva and examined the individual c ... | 1992 | 1624429 |
| genetics of caulobacter crescentus. | | 1991 | 1658564 |