Transfer of plasmid RP1 into chemolithotrophic Thiobacillus neapolitanus.

RP1, a broad-host-range incompatibility group P1 plasmid specifying multiple drug resistances, has been transferred into the chemolithotrophic bacterium Thiobacillus neapolitanus. The ability of T. neapolitanus to receive, express, and transmit RP1-encoded antibiotic resistances was examined. The data show that this obligate chemolithotroph can accept, replicate, and express heterologous plasmid DNA from a heterotrophic bacterium.     

The study of rous sarcoma virus-transformed baby hamster kidney cells using fluorescent probes.

The fluorescent probes pyrene, pyrene butyric acid and N-phenyl 1-naphthylamine have been used to investigate the changes that accompany in vitro transformation of a baby hamster kidney cell line using Rous sarcoma virus. The fluorescent probes which reside in the membrane were used to compare the changes in microviscosity and polarity of the membranes of normal cells with two transformed cell lines. The spectrofluorimetric data indicate that following transformation the probe N-phenyl 1-naphthylamine resides in a more polar environment. However, using the probe pyrene, the yield of excimer indicates decreased mobility of this probe in the membrane of transformed cells. The data also indicate differences between the two transformed cell lines. Laser photolysis was used to study the lifetime of the pyrene probes and the quenching of the pyrene fluorescence in the membrane by several different quenching molecules. The data indicate differences between the three cell lines and suggest that transformation decreases movement within the membrane.     

The study of rous sarcoma virus-transformed baby hamster kidney cells using fluorescent probes

The fluorescent probes pyrene, pyrene butyric acid and $\text{N-}\text{phenyl}$ 1-naphthylamine have been used to investigate the changes that accompany in vitro transformation of a baby hamster kidney cell line using Rous sarcoma virus. The fluorescent probes which reside in the membrane were used to compare the changes in microviscosity and polarity of the membranes of normal cells with two transformed cell lines. The spectrofluorimetric data indicate that following transformation the probe $\text{N-}\text{phenyl}$ 1-naphthylamine resides in a more polar environment. However, using the probe pyrene, the yield of excimer indicates decreased mobility of this probe in the membrane of transformed cells. The data also indicate differences between the two transformed cell lines. Laser photolysis was used to study the lifetime of the pyrne probes and the quenching of the pyrene fluorescence in the membrane by several different quenching molecules. The data indicate differences between the three cell lines and suggest that transformation decreases movement within the membrane.     

Mode of insertion of lipopolysaccharide into the outer membrane of escherichia coli.

A mutant of Escherichia coli that lacks uridine 5'-diphosphate galactose-4-epimerase makes lipopolysaccharide with less carbohydrate than the parent, unless galactose is present during growth. Carbohydrate is dense, and the outer membrane, which contains lipopolysaccharide, was found to be denser when isolated from cells grown with galactose then when galactose was omitted. Cells given galactose after growth in its absence rapidly formed dense regions within the outer membrane that disappeared when galactose was removed. These results indicate that lipopolysaccharide enters the outer membrane nonrandomly at a minimum of 10 to 22 discrete "insertion points." Isopycnic centrifugation provides a method for isolating these regions.     

STING Millennium Suite: integrated software for extensive analyses of 3d structures of proteins and their complexes

Background  

The integration of many aspects of protein/DNA structure analysis is an important requirement for software products in general area of structural bioinformatics. In fact, there are too few software packages on the internet which can be described as successful in this respect. We might say that what is still missing is publicly available, web based software for interactive analysis of the sequence/structure/function of proteins and their complexes with DNA and ligands. Some of existing software packages do have certain level of integration and do offer analysis of several structure related parameters, however not to the extent generally demanded by a user.     

Description of a presumptive hepatopancreatic reovirus, and a putative gill parvovirus, in the freshwater crayfish Cherax quadricarinatus

The redclaw freshwater crayfish Cherax quadricarinatus has a reputation for being hardy and resistant to handling stress. However, in recent years, possibly since 1996, C. quadricarinatus farmers in northern Queensland have noted a decrease in stress resistance in their stock. A presumptive reovirus in the hepatopancreas, and a putative parvovirus in the gills, were associated with chronic mortalities in C. quadricarinatus at one northern Queensland farm. Hypertrophic nuclei with marginated chromatin were observed in gill epithelium in moribund crayfish which had recently been relocated to a laboratory from the holding tank facility on the farm. Affected nuclei appeared to be vacant or contained a faint granular basophilia in H&E stained sections. However, toluidine blue staining revealed a homogeneously granular appearance of the nuclei. Transmission electron microscopy revealed approximately 20 nm diameter virus-like particles within the nucleus. Eosinophilic, Feulgen-negative, cytoplasmic inclusions were observed in distal hepatopancreatocytes in 1 moribund C. quadricarinatus collected from the same on-farm holding tank approximately 6 mo later. This crayfish did not display the gill lesions. Transmission electron microscopy showed that the inclusions contained icosahedral virus particles 35 to 40 nm in diameter. The histopathology and preliminary virus morphology of the presumptive hepatopancreatic reovirus, and the histopathology, ultrastructural pathology and preliminary virus morphology of the putative gill parvovirus, are reported herein.