ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb01166.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb01167.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

One hundred and sixty‐three strains of Gram negative fermentative rods isolated from humans and 60 isolated from diseased snails were identified by a conventional method and by numerical identification on a desk‐top computer. The two methods gave the same identities with 133 ‘human strains’ and 33 ‘snail strains’. The possible sources of the differences in identifications are discussed. The study showed that numerical identification done on a desk‐top computer can be a useful method for routine medical microbiological

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb01168.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

A number of auxotrophic and antibiotic‐resistant mutants ofRhizobium leguminosarumwere isolated and their symbiotic properties examined. Among the auxotrophic mutants tested, only those with an adenine requirement were found to be symbiotically defective and these were all non‐infective. Of the antibiotic‐resistant mutants isolated, only a minority of the rifampicin‐resistant mutants had a modified symbiotic phenotype and this was ineffective. Preliminary evidence suggests that the basis for the resistance in these mutants is a modified DNA‐dependent RNA p

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb01169.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

A modified electrophoretic starch gel technique was developed and applied to the detection of peptidase activity in zymograms of crude extracts of Group N streptococci and extracts of cheese made with these organisms. The method required only 0–36 mg of peptide substrate for each test. Dipeptidase, tripeptidase and aminopeptidase activities were detected in strains ofStreptococcus cremorisandStrep, lactisand in curds and cheeses made with these organisms.Intracellular and extracellular fractions ofStrep, lactisshowed similar peptidase activity but withStrep, cremoris there were fewer peptidases in extracellular fractions. The peptidase composition of curd and cheese extracts of different ages was dependent upon the strain and species of starter streptococcus used in making the chees

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb01170.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Three bacterial strains have been isolated that differ in their ability to degrade polyethylene glycols (PEGs). Strains R and O showed a marked preference for growth on the low and high molecular weight PEGs, respectively, while strain Z utilized mono‐ethylene glycol only. The partial degradation of PEG 200 by strains R and O was studied in some detail and the results suggested that those components of the mixture that were not utilized were converted into acidic derivatives which accumulated in the mediu

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb01171.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Strains representing the taxaCellulomonas, Oerskovia, Brevibacterium fermentans, Corynebacterium manihotandNocardia cellulanswere degraded by acid methanolysis and the non‐hydroxylated fatty acid esters released examined by thin‐layer and gas chromatography. The major fatty acid in all strains was 12‐methyltetradecanoic acid (anteisoC15) which occurred together with otheranteisoacids,isoand straight‐chain acids. The fatty acid profiles of the cellulomonads were distinguished by the presence of 13‐carbon acids and significantly higher proportions of straight‐chain acids than found in the other test strains whose profiles were closely similar to one another. Two‐dimensional thin‐layer chromatography showed that almost identical and very characteristic polar lipid patterns were given by all the organisms under study: the only major components were diphosphatidylglycerol, phosphatidylinositol and two phospho‐glycolipids chromatographing similarly to, but distinguishable from, the mono‐ and diacyl phosphatidylinositol dimannosides characteristic ofNocardiaand other actinomycetes. The accumulated lipid data support the reclassification ofB. fermentans, Cor. manihotandN. cellulansin

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb01172.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

A modification of the serologic mycoplasma growth inhibition test is described. It is based on application of a drop of antiserum directly onto the centre of an inoculated agar plate provided with a slightly concave agar surface. The special apparatus devised for the preparation of these plates is described. This modified serum‐drop method is more sensitive than other growth inhibition tests used today and is equally specifi

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb01173.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

The effect of handling flexible retort pouches has been studied in relation to their integrity and resistance to post‐process contamination (‘leaker spoilage’). Tests were made using a pilot‐plant processing line on which pouches were filled with broth, sealed, heat‐processed and subjected to three post‐process handling treatments. UsingEnterobacter aerogenesas an indicator organism, it was shown initially that rough instead of careful handling during loading of the retort increased the proportion of punctured pouches from 0.06 to 0.27%. The effect of post‐process handling procedures on leaker spoilage was studied using pouches deliberately punctured with a needle of 100 μm diameter. When these pouches were cooled in tap water, unloaded manually from the retort and stored wet, the incidence of post‐process contamination was 90%. With similar pouches which were dried immediately after manual unloading and stored dry, the contamination rate was only 10%, whereas cooling in chlorinated water and dryingbeforemanual unloading reduced the contamination rate of punctured pouches to less than 1%. It was concluded that manual handling of dry pouches presents an acceptable alternative to complete mechanical handling of freshly heat‐processed pouches, which was proposed in a Code of Practice for retort pouches

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb01174.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

The major groups of micro‐organisms on cured woolskins have been correlated with specific curing treatments. No treatment eliminatedBacillusspp. or halophilic bacteria. Of the treatments which eliminated fungi, coliforms and micrococci, biocides and fungicides were significant. Differences were found in microbial population distribution between wool and skin. The minimum curing treatment was salt and naphthalene. The most effective was salt and naphthalene and Benlate. An alternative treatment is salt and sodium fluoride and Busan 3

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1979.tb01175.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY