Abstract: Apparatus for determining the amount of biological material in a fluid medium, typically the concentration of bacteria in a fermentation chamber, has a test cell through which a medium can be passed with bacteria or after bacteria have been removed by filtration. In the test cell a vibratory element is excited to a resonant frequency indicative of density and a comparison of medium density and medium plus bacteria density reveals the bacteria concentration.

Abstract: A method of investigating the condition of biological particles, in particular the fraction of viable cells in a bacteria population involves applying a voltage and monitoring the voltage induced by magnetic induction in a detector coil. The applied voltage is of a variable frequency alternating voltage and is preferably induced in the medium through a drive coil.

Abstract: Apparatus for use in measuring fluid density comprises a fluid carrying helical sample tube 50 made of a conductive material for passing current therethrough. A cylindrical coil fixing sleeve 58 form surrounds the helical sample tube and engages the tube to prevent relative movement of the turns. A high flux permanent magnet 60 is carried on one post 54 and is aligned along the axis of the tube. The magnetic field established by magnet 60 and the pole extension 64 will subject each current-carrying length element of the sample tube to an axial force, the sum of these forces resulting in a bodily axial movement of the sample tube. The sample tube is excited to spring resonance by passing current through the sample tube. The resonant frequency is measured and is indicative of the mass of the fluid contained in the coil and thereby of the fluid density.

Abstract: A process is provided for the production of lymphocytosis promoting factor (LPF), filamentous haemagglutinin (FHA) and at least one fimbrial agglutinogen from a liquid culture of Bordetella pertussis, which comprises the steps of (a) separating the culture into cellular and supernatant fractions, (b) concentrating the supernatant fraction, (c) fractionating the concentrated supernatant fraction to isolate LPF and FHA containing fractions, and (d) isolating at least one fimbrial agglutinogen from the cellular fraction. A vaccine composition may be produced by mixing so-produced LPF, FHA and fimbrial agglutinogens produced.

Abstract: A plasmid selected from(a) a plasmid conferring resistance to tetracyline (Tc.sup.r) and neomycin (Neo.sup.r) on a host, and being built up by the in vitro ligation of a Neo.sup.r non-chimeric plasmid and a Tc.sup.r non-chimeric plasmid,(b) a deletion, insertion or deletion/insertion derivative of a group (a) plasmid, or(c) a rearrangement derivative of a group (a) or group (b) plasmid are disclosed.The host may be a Bacillus, particularly Bacillus subtilis.

Abstract: A process for the affinity chromatographic separation of at least one biological or related substance from a mixture wherein the at least one biological or related substance is bound to a binding material, having a ligand containing at least one of the groups anthraquinone, phthalocyanine or aromatic azo, in the presence of at least one metal ion selected from the group Ca.sup.2+, Sr.sup.2+, Ba.sup.2+, Al.sup.3+, Co.sup.2+, Ni.sup.2+, Cu.sup.2+ or Zn.sup.2+. The preferred metal ions are Co.sup.2+, Ni.sup.2+ and Zn.sup.2+, with Zn.sup.2+ being particularly preferred. The ligand may be linked directly to the matrix or via a spacer arm. The process may be performed at atmospheric pressure or under pressure, especially high pressure (100-3500 psi). The nature of the contact, washing and eluting solutions depends on the substance to be separated.

Abstract: A process for the high pressure liquid affinity chromatographic separation of at least one biological or related substance from a mixture in which the contact, washing and eluting phases are performed on a binding material made from a ligand, containing at least one of the groups anthraquinone, phthalocyanine or aromatic azo, coupled to a matrix through a spacer arm, the binding material being so constructed that at least one biological or related substance is retained on the binding material during the contact and washing phases. In one preferred embodiment the ligand is a reactive dye, especially a triazinyl dye, the matrix is agarose or silica and the spacer arm is a substituted aminohexyl group. The chromatographic procedure is preferably performed at 100-3500 psi, at a flow rate of 0.5-2.0 ml/min. The choice of washing and eluting solutions depends on the material to be separated. However buffer solution to wash the column and a desorbing agent to elute the material are preferred.

Abstract: A process for the production of an aryl acylamidase enzyme involves culturing bacteria of one of the strains Pseudomonas fluorescens ATCC 39005 (or suitable mutants or variants thereof) or Pseudomonas putida ATCC 39004 (or suitable mutants or variants thereof) in a culture medium in which the bacterial strains produce aryl acylamidase and collecting the enzyme containing material, generally the cell material. Preferably the resulting cells are then disrupted, especially by enzymatic treatment, and the aryl acylamidase is separated from the other unwanted substances, generally the other cell constituents.Preferably the culture medium contains N-acylaniline, especially N-acetyl aniline. The N-acylaniline may form part of a complex or defined salts medium.

Abstract: A method for the estimation of an anilide in which the anilide is first hydrolyzed enzymatically to an aniline and then the quantity of the aniline produced is estimated spectrophotometrically preferably colorimetrically.The hydrolysis of the anilide may be catalyzed by any enzyme of the type, EC 3.5.1.13, known as aryl acylamidases. Preferably enzymes isolated from the cells of Pseudomonas fluorescens ATCC 39005 or Pseudomonas putida ATCC 39004 are employed.The aniline may be analyzed, for example, by conversion to an indamine, an indophenol or an indoaniline, followed by colorimetric analysis of the colored quinone-type compound produced. This conversion may take place in the presence of an oxidizing agent, such as a copper (II) salt, and/or a base, such as ammonia.A diagnostic kit to allow the routine use of the above method is also provided.