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91.
92.
H. Seenu Srinatha Subbaraman Sriram Akshay K. Chakravarthy 《Biocontrol Science and Technology》2015,25(7):789-802
Four bacterial and one yeast species, cultured and identified as Stenotrophomonas maltophilia, Acinetobacter sp., Pseudomonas sp. and Ochrobactrum sp. and the yeast as Metschnikowia reukaufii, were isolated from the internal organs of four collections of field-sourced egg parasitoid, Trichogramma chilonis, obtained as parasitised Helicoverpa armigera eggs. Bacteria were identified through 16 rRNA amplification and sequencing. The single species of yeast was identified through internal transcribed spacer sequences. A single bacterial species could be isolated from each of the four T. chilonis collections; however, all four T. chilonis collections yielded the yeast, M. reukaufii. In order to study the influence of the association of each of the bacterial species and the yeast, microbe-free laboratory-bred populations of T. chilonis were fed with the individual cultures and fitness parameters as parasitisation vigour and female bias were studied in T. chilonis over 10 generations. T. chilonis fed with either S. maltophilia or Acinetobacter sp. and Pseudomonas sp. showed a mean percent increase in female ratio of 26.2%, 30% and 30.3% and mean percent parasitisation of H. armigera eggs significantly increased by 38%, 32.2% and 31.3%, respectively. However, T. chilonis fed with Acinetobacter sp. did not positively influence the two T. chilonis fitness factors. The ubiquitous yeast, M. reukaufii, which could be isolated from all four collections of T. chilonis, could significantly increase both female count and percent parasitism ratio by 22% and 65%, respectively. This study has opened the possibility of modulating the parasitisation fitness of laboratory-bred T. chilonis, prior to field release, using microbes associated with them in the wild. 相似文献
93.
94.
Bilachi S Ravindranath Venkatappa Krishnamurthy Venkatarangaiah Krishna Sunil Kumar C 《Bioinformation》2013,9(10):506-510
Chlamydophila pneumoniae is one of the most important and well studied gram negative bacterial strain with respect to community
acquired pneumonia and other respiratory diseases like Chronic obstructive pulmonary disease (COPD), Chronic asthma,
Alzheimer''s disease, Atherosclerosis and Multisclerosis which have a great potential to infect humans and many other mammals.
According to WHO prediction, COPD is to become the third leading cause of death by 2030. Unfortunately, the molecular
mechanisms leading to chronic infections are poorly understood and the difficulty in culturing C pneumoniae in experimental
conditions and lack of entirely satisfactory serological methods for diagnosis is also a hurdle for drug discovery and development.
We have performed an insilico synteny based comparative genomics analysis of C pneumoniae and other eight Chlamydial
organisms to know the potential of C pneumoniae which cause COPD but other Chlamydial organisms lack in potential to cause
COPD though some are involved in human pathogenesis. We have identified total 354 protein sequences as non-orthologous to
other Chlamydial organisms, except hypothetical proteins 70 were found functional out of which 60 are non homologous to Homo
sapiens proteome and among them 18 protein sequences are found to be essential for survival of the C pneumoniae based on BLASTP
search against DEG database of essential genes. CELLO analysis results showed that about 80% proteins are found to be
cytoplasmic, Among which 5 were found as bacterial exotoxins and 2 as bacterial endotoxins, remaining 11 proteins were found to
be involved in DNA binding, RNA binding, catalytic activity, ATP binding, oxidoreductase activity, hydrolase activity and
proteolysis activity. It is expected that our data will facilitate selection of C pneumoniae proteins for successful entry into drug
design pipelines. 相似文献
95.
In vitro induction of multiple shoots and plant regeneration in cotton (Gossypium hirsutum L.) 总被引:5,自引:0,他引:5
D. C. Agrawal A. K. Banerjee R. R. Kolala A. B. Dhage A. V. Kulkarni S. M. Nalawade S. Hazra K. V. Krishnamurthy 《Plant cell reports》1997,16(9):647-652
Induction of multiple shoots in cotton (Gossypium hirsutum L. cv. Anjali-LRK 516) has been achieved with cotyledonary nodes devoid of cotyledons and apical meristems. Explants from 35-day-old seedlings yielded the maximum number of shoots (4.7 shoots/explant) using Murashige and Skoog (MS) basal medium supplemented with 6-benzylaminopurine and kinetin (2.5 mg/1 each). Explants from 35-day-old seedlings raised in glass bottles produced a higher number of multiple shoots (8.3 shoots/explant) than those grown in glass tubes and cultured on the same shoot induction medium. Elongation of multiple shoots was obtained on liquid or agar MS basal medium without phytohormones. In vitro shoots were rooted on half-strength agar-solidified MS basal medium or with 0.05 or 0.1 mg/1 naphthaleneacetic acid. Hardening and survival of tissue culture plantlets was 95% under greenhouse conditions.Abbreviations
BAP
6-Benzylaminopurine
- GA3
Gibberellic acid
- MS
Murashige and Skoog medium
-
NAA
-Napthaleneacetic acid 相似文献
96.
V. Sundararaj K. Krishnamurthy 《Journal of experimental marine biology and ecology》1974,14(3):275-284
The annual variations of phytoplankton pigments were studied from January to December, 1971, at two stations of the local mangrove (Pichavaram) environment. At these two stations, chlorophyll a varied from 2.90 to 35.06; chlorophyll b from 0 to 10.02 and chlorophyll c from 0 to 18.12 μg/l. Plant carotenoids varied from 1.56 to 13.83 MSPU/m3 and phaeopigments from 0 to 12.28 μg/l. The main (primary) peak of chlorophyll a was recorded during March at Station 1, and during June at Station 2.Secondary maxima occurred during June and August at Station 1, and during September at Station 2. During the period studied chlorophyll a was the dominant pigment at both the stations, followed by chlorophyll c and chlorophyll b in that order. The increase in the concentration of pigments was mainly due to the presence of phytoplankton species belonging to the genera such as Coscinodiscus, Rhizosolenia, Thalassiothrix, Melosira, Chaetoceros and Biddulphia. During October, phytoplankton was less and the pigment concentration was also low. 相似文献
97.
98.
Oxidation of guanine (G) and 8-oxoguanine (OG) with a wide variety of oxidants yields the hydantoin lesions, guanidinohydantoin (Gh) and spiroiminodihydantoin (Sp). These two lesions have garnered much recent attention due to their unusual structures and high mutagenic potential. We have previously shown that duplexes containing Gh and Sp are substrates for the base excision repair glycosylase Escherichia coli Fpg (EcFpg). To evaluate the recognition features of these unusual lesions, binding and footprinting experiments were performed using a glycosylase inactive variant, E3Q EcFpg, and 30 bp duplexes containing the embedded lesions. Surprisingly, E3Q EcFpg was found to bind significantly more tightly ( approximately 1000-fold) to duplexes containing Gh or Sp over the corresponding duplexes containing OG. This may be a consequence of the helix-destabilizing nature of the hydantoin lesions that facilitates their recognition within duplex DNA. Though DNA binding affinities of E3Q EcFpg with Gh- and Sp-containing duplexes were found to be similar to each other, hydroxyl radical footprinting using methidium-propyl-EDTA (MPE)-Fe(II) revealed subtle differences between binding of E3Q EcFpg to the two lesions. Most notably, in the presence of E3Q EcFpg, the Sp nucleotide (nt) is hyperreactive toward cleavage by MPE-Fe(II)-generated hydroxyl radicals, suggestive of the formation of an intercalation site for the MPE-Fe(II) reagent at the Sp nt. Interestingly, increasing the duplex length from 18 to 30 bp enhanced the excision efficiency of Gh and Sp paired with C, G, or T by EcFpg such that these substrates are processed as efficiently as the signature substrate lesion, OG. Moreover, the base removal activity with these two lesions was more efficient than removal of OG when in a base pairing context opposite A. The high affinity and efficient activity of EcFpg toward the hydantoin lesions suggest that EcFpg mediates repair of the lesions in vivo. Notably, the facile activity of EcFpg toward Gh and Sp in base pairing contexts with G and A, which are likely to be present after DNA replication, would be detrimental and enhance mutagenesis. 相似文献
99.
100.