Biomaterial Database

Identification of a gene cluster involved in flagellar basal body biogenesis in Caulobacter crescentus. 1987

K M Hahnenberger, and L Shapiro

The bacterial flagellum is a complex structure composed of a transmembrane basal body, a hook, and a filament. In Caulobacter crescentus the biosynthesis and assembly of this structure is under temporal and spatial control. To help to define the order of assembly of the flagellar components and to identify the genes involved in the early steps of basal body construction, mutants defective in basal body formation have been analyzed. Mutants in the flaD flaB flaC gene cluster were found to be unable to assemble a complete basal body. The flaD BC motC region was cloned and the genes were localized by subcloning and complementation analysis. A series of Tn5 insertion mutations in the flaD BC region were mapped. Complementation analysis of the Tn5 insertion mutants indicated the existence of at least four transcriptional units in the region and identified the presence of two new genes designated flbN and flbO. Mutants in flbN, flaB, flaC and flbO were unable to assemble any basal body structure and are likely to be involved in the early steps of basal body formation. The flaD mutant, however, was found to contain a partially assembled basal body consisting of the rod and three hook-distal rings. All of the mutants in this cluster exhibited pleiotropic effects on the expression of other flagellar and chemotaxis functions, including the level of synthesis of flagellins, the hook protein and hook protein precursor, and the level of chemotaxis methylation.

UI	MeSH Term	Description	Entries
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D010641	Phenotype	The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.	Phenotypes
D010957	Plasmids	Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.	Episomes,Episome,Plasmid
D011548	Pseudomonadaceae	A family of gram-negative bacteria usually found in soil or water and including many plant pathogens and a few animal pathogens.	Azomonas,Azomonas agilis,Azotobacteraceae
D003001	Cloning, Molecular	The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.	Molecular Cloning
D004251	DNA Transposable Elements	Discrete segments of DNA which can excise and reintegrate to another site in the genome. Most are inactive, i.e., have not been found to exist outside the integrated state. DNA transposable elements include bacterial IS (insertion sequence) elements, Tn elements, the maize controlling elements Ac and Ds, Drosophila P, gypsy, and pogo elements, the human Tigger elements and the Tc and mariner elements which are found throughout the animal kingdom.	DNA Insertion Elements,DNA Transposons,IS Elements,Insertion Sequence Elements,Tn Elements,Transposable Elements,Elements, Insertion Sequence,Sequence Elements, Insertion,DNA Insertion Element,DNA Transposable Element,DNA Transposon,Element, DNA Insertion,Element, DNA Transposable,Element, IS,Element, Insertion Sequence,Element, Tn,Element, Transposable,Elements, DNA Insertion,Elements, DNA Transposable,Elements, IS,Elements, Tn,Elements, Transposable,IS Element,Insertion Element, DNA,Insertion Elements, DNA,Insertion Sequence Element,Sequence Element, Insertion,Tn Element,Transposable Element,Transposable Element, DNA,Transposable Elements, DNA,Transposon, DNA,Transposons, DNA
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
D005407	Flagella	A whiplike motility appendage present on the surface cells. Prokaryote flagella are composed of a protein called FLAGELLIN. Bacteria can have a single flagellum, a tuft at one pole, or multiple flagella covering the entire surface. In eukaryotes, flagella are threadlike protoplasmic extensions used to propel flagellates and sperm. Flagella have the same basic structure as CILIA but are longer in proportion to the cell bearing them and present in much smaller numbers. (From King & Stansfield, A Dictionary of Genetics, 4th ed)	Flagellum
D005798	Genes, Bacterial	The functional hereditary units of BACTERIA.	Bacterial Gene,Bacterial Genes,Gene, Bacterial
D005810	Multigene Family	A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed)	Gene Clusters,Genes, Reiterated,Cluster, Gene,Clusters, Gene,Families, Multigene,Family, Multigene,Gene Cluster,Gene, Reiterated,Multigene Families,Reiterated Gene,Reiterated Genes